MAP sensor questions

[prkaye]

I'm trying to puzzle-out how to connect the Dynon MAP sensor using the IE VMP INSTALL kit I got from Vans.

1) It looks like the SS hose I got is supposed to connect to cylinder #3? Problem is, I have routed my primer line to cylinder #3. Can I use Cylinder #4 instead for MP? (what would you do for MP if you wanted primer lines in every cylinder?)

2) The Dynon documentation recommends a restrictor fitting. THe fitting I got from vans that goes into the cylinder is just a plain old AN816-4D fitting. Is there a restrictor version of this available? Part number?

Thanks!!

Phil

[AltonD]

Van's has a restrictor fitting. You do need it, otherwise, your indicated pressure will jump all over the place.

Any cylinder should be fine.

Other than the stainless hose, I pretty much chunked the rest of the Van's kit. Here is what mine ended up like:
http://www.mykitlog.com/users/displa...g=59778&row=21

I got the fancy Tee from the aviation ailse at the local autoparts store.

[kiwipete]

Phil

You need a few small hole in the restrictor otherwise you'll get flucations. In the end I used a cigarette filter in the line to dampen out the flucations plus a metal filter screen to ensure the cigarette filter couldn't move.

Do a quick search as this topic comes up often.

Peter

[prkaye]

You need a few small hole in the restrictor otherwise you'll get flucations. ..I used a cigarette filter

If this is really a problem, surely the aviation industry has come up with a proper fitting to solve the problem?

[Tom Martin]

Phil
It is very easy to modify the AN fitting at the cylinder. And yes, #4 cylinder will work just as well. On the flared end of the fitting drill the hole using a #30 drill. Drill it out deep enough for a #4 universal rivet to fit. A -3 length will be long enough. Put a dab of red lockite on the rivet and tap it into the hole. Now take the smallest drill you can find, 1/16th will work, but smaller would be better, and drill through the rivet. Now grind off the head of the rivet until it mimics the flare of the fitting. Thats it. I have used this technic on numerous airplanes, it works and can be done faster then the time it takes to order a fitting.

[RV8RIVETER]

Good timing on this thread.

The Mooney my engine came from tapped the #2 cyl for MAP. Is there any reason I can't Tee it into the 1/8 NPT port on the bottom of the intake, right behind the fuel servo, tapping the horizontal tee port making sure the sensor box is higher than the intake ?

[alpinelakespilot2000]

Phil-
If you bought Van's firewall forward kit and an engine from Aerosport, you may already have an extra fitting. Check your firewall forward kit for an extra black 45-degree VA-128 fitting. You need one for your fuel pump pressure outlet and one for your oil pressure outlet on the engine. Van's provides 2 in the kit, but my Aerosport already had one in the oil pressure outlet.
Hope this helps.

[Brantel]

I tried to use a spare on my engine and it would not fit because it would not turn due to hitting the cylinder fins.

[Doug]

Originally Posted by Tom Martin

Phil
It is very easy to modify the AN fitting at the cylinder. And yes, #4 cylinder will work just as well. On the flared end of the fitting drill the hole using a #30 drill. Drill it out deep enough for a #4 universal rivet to fit. A -3 length will be long enough. Put a dab of red lockite on the rivet and tap it into the hole. Now take the smallest drill you can find, 1/16th will work, but smaller would be better, and drill through the rivet. Now grind off the head of the rivet until it mimics the flare of the fitting. Thats it. I have used this technic on numerous airplanes, it works and can be done faster then the time it takes to order a fitting.

Do you follow the same procedure for your oil an fuel pressure restrictors? I like the approach and need to modify my fitting so I can mount the engine. I'd rather not wait the 5 day turnaround for parts from Vans.

I would expect you drill the tapered end to 3/16" and push in (+loctite) a drilled #6 universal rivet. Please confirm.

Doug

[breister]

Just a note to those using cigarette filters - some have found that the material eventually gets sucked into the engine. It probably won't hurt anything, but it won't help, either.

Probably best to go with a restriction fitting.