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Found the Cause and now Need the Fix

todehnal

Well Known Member
I've been fighting vibration, short spark plug life and very dirty oil.
I got a tip from the Rotax booth at Oshkosh and he convinced me that I had an intake leak. So, when I got home, I built a simple smoke machine. I hooked it it and it quickly became obvious that I do, indeed have an itake leak. Both carb rubber sockets have leaks coming from between the rear surface of the drip pans, and the carb sockets.

Before leaving Oshkosh, I stopped by Lockwood and picked up 2 new carb sockets, and the parts lady she asked if I was using drip pans. When I told her that I was, she said that I also needed 2 new "O" rings and 2 gaskets, which she provided for me.

After getting home, I refered to my buildng plans and found no mention of adding a gasket. I then went to the parts manual to determine the exact orientation of the "O" rings and gaskets. The figure: 73-10-00-1 shows the gasket replacing the "O" ring and relocating the "O" ring to the surface between the socket and the drip pan. NO WAY WILL THIS WORK ! The layout of the figure must be decieving.

If anyone knows and could share the exact orientation of these parts, it would be greatly appreciated. This may also help someone else who is doing the 5 year rubber socket replacement. Thanks..........Tom
 
I would suggest using extreme care in reassembling as illustrated in the parts manual (IPC)
I know of at least one engine that was destroyed because of a bad induction leak when the o-rings were installed on the same side of the drip tray as the carb socket.

The RV-12 ULS KAI specifically shows the o-ring on the manifold side of the drip tray, and nothing additional added on the carb. socket side.
The standard carb. socket has an integral o-ring molded into it which takes care of sealing on that side (unless you introduce a second o-ring that cant be kept in the proper position).

EDIT - I just looked through our archive of superseded Rotax documentation and found that in the 2010 version, it also showed a gasket but it was co-located with the o-ring on the manifold side of the drip tray.

Additional edit - I have an e-mail out to our USA Rotax tech. support contact. I will post here what I find out.
 
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O-ring on the manifold side of the drip tray, and nothing additional added on the carb. socket side. The standard carb. socket has an integral O-ring molded into it which takes care of sealing on that side.

My RV-12 Rotax 912ULS is assembled as described above.

Assembly is done dry, but if you like, you good use some O-ring grease sparingly...
 
Scott, thanks so much for persuing the best fix for this leak. The smoke test clearly showed the leak to be between the drip tray, and the carb socket. I would have thought that the integral ring molded into the rubber sockets would have sealed these mating surfaces, but both of mine are leaking. Mearly adding the gasket to the front of the drip tray surface will not be beneficial to my situation. I think that I would need to replace the original "O" rings, add the gaskets between the drip tray and the replacement rubber socket that I bought. However, I will not move forward until I hear back from your inqueeries. Thanks..........Tom
 
I've been fighting vibration, short spark plug life and very dirty oil.
I got a tip from the Rotax booth at Oshkosh and he convinced me that I had an intake leak. So, when I got home, I built a simple smoke machine. I hooked it it and it quickly became obvious that I do, indeed have an itake leak. Both carb rubber sockets have leaks coming from between the rear surface of the drip pans, and the carb sockets.

Great post! I’m interested in the outcome.

Would you mind explaining how you built the “simple smoke machine” and how you hooked it up?
 
Great post! I’m interested in the outcome.

Would you mind explaining how you built the “simple smoke machine” and how you hooked it up?

No problem Walt, That is if you can keep from laughing at this.
I started with a half gallon jar with a wide mouth metal lid. I drilled 2 holes just under the size of tubless tire rubber valve stems (valve stems removed) and popped them in from the bottom with a pair of pliers. I had an cheap old straight electric soldering iron, cut off the cord and installed it through another hole that I drilled into the lid and re-attached the cord with wire nuts. The idea was to keep the holes in the lid sealed as well as possible. You could use a high temp silicone sealer if you wanted

Now to use it: You will need a bicycle tire pump, a couple of rubber gloves, a 3 or 4 foot length of plastic tubing about 1/4" size, a couple of old shop towels and some mineral oil or baby oil will work just as well.
I popped out both carbs and replaced them with the rubber gloves to seal the intake ports. I cut off one finger tip and inserted one end of the plastic tubing into it and clamped it with a hose clamp. The other end was pushed tightly over one of the valve stems. I attached the tire pump to the other rubber valve stem. Wrap a few old shop towels around the tip of the soldering iron and soak them very well with the mineral oil. The soldering iron and old soaked rags go ito the jar and close the lid tightly. Now plug in the soldering iron and wait about 5 minutes while the jar fills with smoke. Start slowly operating the tire pump and watch the rubber gloves inflate. After a few minutes you will see smoke if you have an intake leak.

Are you laughing yet? It really worked for me and it led me directly to the source of the leaks. Hope this helps. Oh, my shirt still smells like smoke. ......Tom
 
Another problem with using the IPC as an assembly guide is that you have to make sure you understand the vendor's method for annotating applicability for different model/year parts.

I know of more than one occasion when someone tried to put a newer part in an older assembly that was no longer applicable.
 
Scott, thanks so much for persuing the best fix for this leak. The smoke test clearly showed the leak to be between the drip tray, and the carb socket.

When manifold leakage is fixed please report back on vibration, short spark plug life and very dirty oil. I'll be interested if fix solves any of these problems...
 
I wonder why the drip tray installed between the rubber socket and the intake?

Wouldn't it be better to attach it on other side of the rubber socket keeping it in place with the same bolts as the socket?

img_6300.jpg
 
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I wonder why the drip tray installed between the rubber socket and the intake?
this may not have been the best choiceo attach it on other side of the rubber socket keeping it in place with the same bolts as the socket?

img_6300.jpg

I agree that this may not have been the best drip tray mounting choice. Some Rotax powered aircraft do mount their drip trays without effecting the carb seals. I'm hoping that the added gasket, that was recomended by a Rotax rep at Oshkosh will solve the sealing problem. I will post the results....Tom
 
When manifold leakage is fixed please report back on vibration, short spark plug life and very dirty oil. I'll be interested if fix solves any of these problems...

Jim, I will post the results. One other symtom that I didn't mention was that I have higher than normal EGT reading. In fact, occationally I have seen them up in the yellow zone, intermittantly and for short periods on the Skyview display at certain power settings.
 
I suspect that it doesn't make much difference but according to the KAI (Page 46-07) the carb-to-rubber socket attachment clamp should be installed as follows:

Step 4: Install the band clamp (C) onto the carburetor flange assembly. See Figure 4. The clamp lugs and screw must be placed at the bottom or 6 o'clock position with the screw head facing outboard.
 
Like you david, I don't think that it would make any difference, but that is the that I had them, and will do them this time as well....Tom
 
I would suggest using extreme care in reassembling as illustrated in the parts manual (IPC)
I know of at least one engine that was destroyed because of a bad induction leak when the o-rings were installed on the same side of the drip tray as the carb socket.

The RV-12 ULS KAI specifically shows the o-ring on the manifold side of the drip tray, and nothing additional added on the carb. socket side.
The standard carb. socket has an integral o-ring molded into it which takes care of sealing on that side (unless you introduce a second o-ring that cant be kept in the proper position).

EDIT - I just looked through our archive of superseded Rotax documentation and found that in the 2010 version, it also showed a gasket but it was co-located with the o-ring on the manifold side of the drip tray.

Additional edit - I have an e-mail out to our USA Rotax tech. support contact. I will post here what I find out.

Response received <pasted below> and the answer was just as I suspected.

Dear Scott,

Glad to hear from you and I do remember this person, we suggested he inspected that area due to his complaint

I don’t think the IPC is correct, I agree with you that the O-ring needs to be on the manifold side, the gasket should be between the O-ring and the heat shield

I will get Rotax to comment on this, please continue doing as you were, I would only add the gasket

I hope this helps and I will let you know when Rotax comments

Best regards
 
I agree that this may not have been the best drip tray mounting choice. Some Rotax powered aircraft do mount their drip trays without effecting the carb seals. I'm hoping that the added gasket, that was recomended by a Rotax rep at Oshkosh will solve the sealing problem. I will post the results....Tom

This drip tray mounting method is actually as designed by Rotax.
The depiction in the IPC is of the Rotax part # drip tray and how it should be installed (with the exception of what I believe is an error regarding the position shown for the o-ring).

A drip tray that mounted to the aft side of the carb. socket using the two mounting studs and nuts would be destroyed by vibration in a very short time because there is only room for it to have very small ears to attach at the studs.

There is now 700+ RV-12's flying, with the majority of them having the ULS engine. This is the first instance I am aware of where an induction leak at the carb socket was causing an engine performance problem when the parts were assembled as directed in the KAI.

How old are the carb sockets? They are one of the parts included in the 5 year rubber parts replacement schedule. If they have been replaced, were the new ones genuine Rotax parts or the aftermarket ones that are available?
 
This is the first instance I am aware of where an induction leak at the carb socket was causing an engine performance problem when the parts were assembled as directed in the KAI.

I'm having a tough time figuring out how induction leak at both carbs is producing vibration, short spark plug life and very dirty oil as OP states.

I'll keep an open mind and wait for final report.
 
This drip tray mounting method is actually as designed by Rotax.
The depiction in the IPC is of the Rotax part # drip tray and how it should be installed (with the exception of what I believe is an error regarding the position shown for the o-ring).

A drip tray that mounted to the aft side of the carb. socket using the two mounting studs and nuts would be destroyed by vibration in a very short time because there is only room for it to have very small ears to attach at the studs.

There is now 700+ RV-12's flying, with the majority of them having the ULS engine. This is the first instance I am aware of where an induction leak at the carb socket was causing an engine performance problem when the parts were assembled as directed in the KAI.

How old are the carb sockets? They are one of the parts included in the 5 year rubber parts replacement schedule. If they have been replaced, were the new ones genuine Rotax parts or the aftermarket ones that are available?

Hi Scott, Thanks for your research and response. I am fighting several issues. The most concerning is the high EGT on the right (1,3) bank. It is running about 100 degrees hotter than the left and may well be the cause of the spark plugs short life, followed by increased vibration, carb shake and flooding resulting in black oil. That led me to the smoke test in search of an intake leak. I installed new rubber carb sockets, "O" rings, and added the gaskets per the description that you sent. All parts are direct from Lockwood Aero. Additionally I installed new spark plugs and changed the oil, both of which only have about 8 hours on them. I also did a carb balance which dialed in perfectly. But I still have the high (100 degrees higher} right EGT than the left. These are new EGT probes and I have swapped them to verify that they are reasonably accurate. The engine is now running smooth at idle and in the mid 3000s, but I still feel a vibration at cruise, a well as off idle, even though the carb balance is right on. Both carbs recently went through a rebuild at Lockwood. Also the mag check is excellent. Cruise EGTs are roughly showing 1340 left and 1440 right. My test flight only lasted about 15 minutes, but I plan to pull the plugs in the morning to see if I can get a read on them. This is driving me crazy and has plagued me for more than 2 years now. Really appreciate your help............Tom
 
I think most folks see higher EGT on right side – I do. I think perhaps the oil tank on the right side influences the right rear exhaust tube which is in close proximity.

Here are two photos of my D180 at different OAT’s. On the 37F day the right EGT is almost 100F higher than left. On the 67F day the EGT’s match more closely. For what it’s worth…
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A vacuum leak usually generates a lean air / fuel mixture ratio. This would be inconsistent with fouled plugs and dirty motor oil in only 8 hours.

Some recent problems observed with Carburetors are rebuilt carbs by Lockwood, or CPS, don't remember which, with the chokes installed backwards, and poor epoxy on some very small fine ports on a couple of the Bing carburetors, that were generating air leaks and fuel mixture problems.

Do a Google search to see what shows up with those particular words in the search.
 
With COVID this past year, I haven’t flown in my friend’s RV-12. We fly Loose formation a lot and compare temps while chit-chatting on 122.75. His exhaust temps are always 100F higher than mine at cruise power settings. His engine is always in mid to high 1400’s EGT.
 
Thanks Jim for the photos and input. Yesterdays short flight was on an 80 degree day with CHTs around 190 and EGTs about 1340 L and 1440 R. I think the fouled plugs come later, after the lean mixture and high temps cause them to deteriorate. Then the roughness gets worse, the carbs shake and flood the cylinders causing the oil to turn black. And yeah, this all happens in 6 to 8 hours. Frustrating! I may do another smoke test to see if I can identify another intake leak. I have new intake manifold "O" rings and I may just go ahead and replace them as well. but that will have to wait until Saturday morning......Tom
 
Per your photo in post #11… check rubber hose for cross-over balance tube. Hose appears to have a bend and I think it should be fairly straight routing. Also, the hose clamp on the manifold fitting is very poor quality as supplied by Rotax. I suspect a vacuum leak is possible at this location. When I installed High Performance Silicone heater hoses, I replaced this clamp. You can search 5-year Replacement Rubber Thread and find my posts.

O-ring for rubber carb socket maybe squished flat over time so replacement with new is good discission. As mentioned in previous post, you can use O-ring silicone grease very sparingly if concerned about sealing.
 
I may have been premature in saying that I didn't solve anything by fixing the intake leaks at the drip tray socket connections. It did make a difference in the carb balance effect, and the idle. Yes, I still have a high EGT on the right bank, but that needs more explanation. First, sometime back during a 1 hour breakfast fight, I noticed a sudden change in the exhaust tone. It startled me, but the engine seems to continue to run fine, it just had a deeper tone. I pulled the muffler and shook it, but found nothing loose inside, so I reinstalled it and continued to run it. Very shortly after that I started having rough running, eating spark plugs and having very dirty engine oil. I chased my tail with carb rebuild, ignition system swaps and finally leading to an intake leak that seems to be behind me now.

Today, I pulled the spark plugs for a read after only about a 30 minute run yesterday. They were all burning quite evenly, although a bit sooty, which has been normal. So I took it for a test flight. At idle both EGTs are normal. Even up to 3000 RPM they remain pretty close. After takeoff I noticed the sharp increase on the right EGT, which is on cylinder #2. Retarding the throttle had little effect. With power retarded, and with the nose pointed down hill to raise the RPM I still have high right EGT. The only way to reduce the EGT reading is to reduce the engine RPM. In this case, just raising the nose and not touching the throttle, which reduced the RPM did the trick.

So, is there any way that a shifted baffle inside the muffler could cause such a condition. And if it could, is there any way to test it, other than paying $1300 for a replacement test muffler? I think that I may just be on to something here. Any thoughts appreciated.....Tom
 
As mentioned above... higher (100F) EGT on right side is seen by lots of folks running 912ULS in RV-12 when engine is making high power. I wouldn't worry about it.
 
You might consider replacing the throttle springs with the newer ones, and take a look at the throttle lever wher it hits the stop. It could be the picture, but it looks like the stop has worn a slot into the throttle lever.

Vic
 
I really appreciate the comments from Jim, Mich and Vic. I now have both the torsion and a light pull springs on the carb throttle levers which overcomes any play in the cable movement resulting in excellent carb balance. I guess my fixation with the EGT disparity is the fact that I am seeing a huge change from what they used to read. I have a lot of respect for Mike Busch and I read the listed article thoroughly. The other issue is that I am having a hard time wrapping my head around the fact that my high EGT reading worsens with RPM, not throttle. Also, as the EGT goes up, so does the vibration. That is why I was leaning toward a restricted airflow through the muffler. My next move is to make a runup test with, and without the muffler to see if that effects the EGT balance. Of course, I can't cowl it with the muffler off, nor fly it with the cowl off, so i am restricted to information gathered form ground runs. Also, that change in engine sound during a cruise flight is still haunting me. I'll report my findings.
 
Not sure what fuel you're running, but I've recently seen a couple EAA LSA Webinars on the Rotax 912 that describe lead collecting in the muffler when using Decalin with 100LL. This unexpected side-effect cut the life of the muffler in half and required a replacement muffler. For that reason, the webinar host (Paul Shuch) now advises against using Decalin. This may not apply to your scenario, but I thought I'd mention it since you suspect a possible muffler issue.
 
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Thanks Brad, but I exclusively use premium 93 octane alcohol free auto fuel. It is difficult to find in our area which requires me to make a 100 mile round trip run with my 55 gal barrel every month or so. I keep hoping for lead free avgas to be the norn at FBOs someday. That will sure be a welcomed change. I plan to ground run it today with the muffler off to see how that works. ...Tom
 
Thanks Brad, but I exclusively use premium 93 octane alcohol free auto fuel. It is difficult to find in our area which requires me to make a 100 mile round trip run with my 55 gal barrel every month or so. I keep hoping for lead free avgas to be the norn at FBOs someday. That will sure be a welcomed change. I plan to ground run it today with the muffler off to see how that works. ...Tom

A muffler might be cheaper than a 600 hr inspection on the gearbox, plus clutch parts due to lead contamination, due to use of 100LL, not to mention the mess it leaves inside the crankcase or behind the rings, inside the lands, gumming things up back there. Talk to someone that's rebuilt Rotax engines with new piston kits, for what that's like. Just saying, mufflers aren't really very mechanical, compared to the price of parts on a Rotax.

Rotax has stated that 91 Octane premium is more than sufficient for the 912 ULS, so finding 93 really isn't necessary.
 
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I'm the same as others.. My EGTs are normally about 100 higher on the right side too.. I had read this was common, so never worried about it since everything seems to be okay.

Sounds like you're left with vibration issues. Since your carbs are balanced, which would be the first thing I'd suspect, have you verified that your prop is balanced?
 
A muffler might be cheaper than a 600 hr inspection on the gearbox, plus clutch parts due to lead contamination, due to use of 100LL, not to mention the mess it leaves inside the crankcase or behind the rings, inside the lands, gumming things up back there. Talk to someone that's rebuilt Rotax engines with new piston kits, for what that's like. Just saying, mufflers aren't really very mechanical, compared to the price of parts on a Rotax.

Rotax has stated that 91 Octane premium is more than sufficient for the 912 ULS, so finding 93 really isn't necessary.

I was buying 91 non ethanol fuel locally at a Casey's and received a old batch of gas. What a foul odor. I guess the demand was not that great. I buy my 93 from a distributer that caters to an Amish community and they use lots of non ethanol 93. Always fresh and I don't mind the trip since I know what I am getting.
 
I'm the same as others.. My EGTs are normally about 100 higher on the right side too.. I had read this was common, so never worried about it since everything seems to be okay.

Sounds like you're left with vibration issues. Since your carbs are balanced, which would be the first thing I'd suspect, have you verified that your prop is balanced?

You may be right Joe. It is just bugging me for 2 main reasons. 1, at my normal 5300 RPM cruise, if I lower the nose just a little to reduce altitude the Skyview indication moved into the yellow zone and it did not do that for the first 400 hours of operation. 2, Even with reduced throttle in a glide the approaches 5400 RPM, I am in the yellow.

I pulled the muffler today, use mirrors, vacuum and high air pressure air to test for any obstuction in air flow and found nothing.

I must say that after replacing the carb sockets, and re-balancing the carbs, it runs a whole lot better. I still have some vibration and cruise, but not enough to ground me. I have an appointment with Vic Syracuse and his staff at Base Leg aviation in a couple of weeks. He was confident that they could find the cause of the rough running and vibration as well as to install new Teflon hosed and the other rubber 5 year rotax items. I will ask him to do the prop balance as well. Hopefully that will be the end of my miseries. The way it was running before, I was not comfortable with a 2 1/2 hour flight down there. Now, I feel good to go, even though it is not perfect.........Tom
 
I buy my 93 from a distributer that caters to an Amish community and they use lots of non ethanol 93. Always fresh and I don't mind the trip since I know what I am getting.

A little off-topic, but it’s a slow day… I saw “Amish” and had a good laugh. When my granddaughters visit, if any severe behavioral problems crop up that need attention – I make them “Amish”- no electricity, no WiFi, no lights in their bedroom. Threatening “Amish” carries a little bit of weight to it…
 
Yeah Jim, your Dad's Amish threat sounds like a terrific attention getter for any unfavorable behavior.

So, I seem to be down to 2 issues with my Rotax, and they are more than likely related. I still have some vibration issues and I am still very fuel rich. At the end of my first 200 hours of flight, close spark plug examination showed zero wear and perfect burn. I replaced them anyway as recommended. The next 200 hours have been a disaster. Part of that was unrecognized heavy floats, followed by chasing my tail to figure it out, then more bad floats, followed by more bad floats. with a carb rebuild by Lockwood thrown in the middle. The really bad part of their service was that I was chasing a condition that appeared to be generated by the right carb. When I got them back and installed them, I still had a problem but it appeared to be moved to the left side. I absolutely identified that the carb domes were swapped by a fuel line rub mark. What other parts were swapped I can only guess. I did call them on it and they did investigate, but then told be that it didn't matter as the parts were interchangeable and all parts were in serviceable condition. I would agree with that had I not been chasing a problem with one carb.

I feel confident that I can make the flight down to GA without an issue, but I will carry an extra set of spark plugs that are prepped and ready to install, should I need them. I sure hope that the folks at Base Leg aviation can figure this out for me...............Tom
 
Tom,
As NinerBikes suggested some posts back, you need to take a close look at the carb choke assembly on the side thats running rich. Since your troubles started around the time you had the carbs rebuilt, its possible the choke was assembled incorrectly by Lockwood (would not be the firs time from what I have read).
Alex
 
Best practice when rebuilding carbs is to disassemble / reassemble one at a time. This way no parts get interchanged.

Perhaps check circlip position on main needles. I forget… I think clip should be in 2nd groove from top. Somebody can confirm or correct me here. In any event, if needle is positioned incorrectly, you will experience lean (needle low) or rich (needle high).

SB-912-073 confirms circle position is in 2nd groove from top on main needle.
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I realize you just had them rebuilt but this might be worth looking at.

https://legacy.rotaxowner.com/si_tb_info/serviceb/sb-912-073.pdf

"Due to deviations in the manufacturing process a partial fracture of the circlip may occur. This fracture might lead to a crack/ total fracture of the circlip which in consequence may lead to a malfunction of the carburetor. Possible effects might be rough engine running or an unusual engine operating behavior."
 
Thanks guys. I did pull the dome tops off of both carbs to check the circlip position. Both carbs had good circlips and they were in #3 position, which is the proper position. I also checked the clocking of the diaphragms and slides. This all looked good as well with the diaphragm tabs in the notches, and the slides were both free. I did find that the idle circuit mixture screws were not at the 1 1/2 turns out position, which I corrected. The only suggestion that I have not done is to disassemble the choke control, but I did verify that the centerpunch mark on the shafts are in the correct position, which indicates that they are assembles properly. I sort of discounted the choke as the problem because it seems to idle so good. It is only in the upper mid and full throttle positions that seem to be problematic. I also spend a couple of hours cleaning black soot off of the belly, again verifying that it is running way too rich.......Tom
 
See drawing in post #39 above. Circlip belongs in 2nd groove from top. If you have clips installed in 3rd groove from top it is setting the needle taper higher in the main jet and engine will run rich.
 
Circlip position

Here is the whole calibration drawing. Circlip position depends on engine type. The picture in the SB could be misleading.

i-JDk7KxF-X2.png
 
Good info Tony... My clips are installed in position #2 as are two other 912 ULS RV-12's that I know of. All is well with no rich mixture operation. If the OP has rich mixture he can certainly try to lower the needles one notch and achieve slightly more lean operation condition on the main jet.
 
I just now took the needle out of a 912 ULS carb that I know the complete history. This carb came new with a new 912 from Van’s in 2010 and the carb has never been rebuilt, or even taken apart.

This engine has always run perfectly.

The Circlip is in the number 3 position.
 
Position #2 is ok if you regularly fly at high altitude, Colorado etc. The normal position is #3, counting from the top.
 
Thanks guys. I did pull the dome tops off of both carbs to check the circlip position. Both carbs had good circlips and they were in #3 position, which is the proper position. I also checked the clocking of the diaphragms and slides. This all looked good as well with the diaphragm tabs in the notches, and the slides were both free. I did find that the idle circuit mixture screws were not at the 1 1/2 turns out position, which I corrected. The only suggestion that I have not done is to disassemble the choke control, but I did verify that the centerpunch mark on the shafts are in the correct position, which indicates that they are assembles properly. I sort of discounted the choke as the problem because it seems to idle so good. It is only in the upper mid and full throttle positions that seem to be problematic. I also spend a couple of hours cleaning black soot off of the belly, again verifying that it is running way too rich.......Tom

Soot off the belly? I had that once when I oiled my air filter with the squirt type bottle. There ended up being way too much oil in the air filter and it sucked the excess oil into the carb and ran it through the engine out the exhaust and on to the belly. It also fouled the plugs somewhat and made them appear to be running rich. If you recently, ie. before all these troubles, cleaned and oiled your air filters. Take them out and clean them with the proper cleaner and then get a spray bottle of oil and VERY lightly spray them.
 
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Hey Bruce, thanks for your experience. I did recently service my air filters, but I used the official K & N kit following their instructions to the letter. I did have the over rich problem before servicing the air filters, and the filters look like new and are not wet. Basically you use their cleaner, thoroughly rinse, then dry them overnight, lightly oil and allow another overnight absorption. Always worked well in the past.... Tom
 
Finnaly!! Found The Problem

It's been a real struggle and I thought I found the problem. I posted but then deleted the post as it was premature and Tony pointed out the error in my logic
Sorry for the mis information

Maybe next time.......Tom
 
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Perhaps, in the future, when anyone packs their Carburetors for a rebuild, leave instructions inside the box that you want the carburetors rebuilt one at a time, as it's too easy to mix up the parts after sniffing too much carburetor cleaner. :D
 
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