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  #11  
Old 01-12-2020, 11:56 PM
isosceles isosceles is offline
 
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Location: Fremont
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Quote:
Originally Posted by Canadian_JOY View Post
... the two ignition leads coming from the P-Mag appear to be touching both the engine mount and the oil cooler line.
... EMagAir recommends these ignition leads be isolated from any contact with metal since that contact could result to arcing through the lead
Please elaborate... breakdown voltage for silicone is something like 20KV/mm
(https://chemistry.mdma.ch/hiveboard/...l_strength.pdf) while air has only ~3KV/mm. You would need roughly 10 times more air than silicone to at least match silicone. Assuming at least 3 mm of silicone insulation around the core you would need around 20mm clearance to all metal parts which is insane and not realistic.

One need to avoid running two ignition wires in parallel or along a flat metal part, but for a different reason.
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  #12  
Old 01-13-2020, 12:07 AM
scsmith scsmith is offline
 
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About purging air from the sensor lines.....

True that it is not necessary, but if you like to see your oil pressure indication rise quickly on engine start, purging the air will certainly help that.

With air in the sensor head space, it can take several seconds to pump enough volume of oil through the pin-hole restricter on the crank case to compress the air up to pressure.
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  #13  
Old 01-13-2020, 12:42 AM
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rv8ch rv8ch is offline
 
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Thanks for the feedback. This is a kind of old picture but the best one I had of these sensors.

I did decide to not purge the air as suggested, and it seems to work fine.

The tip on the sharp corners is a good one - will check that. I have not removed the oil filter yet - I think I have enough space, but will confirm.

I think I have pretty good clearance on all the ignition wires now - they have gone on and off a few times since this photo was taken.

I also would love to hear about better pressure sensors - these VDO sensors seem to be really for what they do, but they are what GRT recommended. If I change them, I'd like to use something that GRT support. I am currently faced with changing the temperature sensor since the one I used is for a different software version on my EIS 4000. :S

Thanks again for the tips!
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  #14  
Old 01-13-2020, 05:21 AM
svyolo svyolo is offline
 
Join Date: Oct 2017
Location: bellingham, wa
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I have a couple of VDO oil pressure transducers on Subaru engines, mounted on the engine, that are almost 20 years old.
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  #15  
Old 01-13-2020, 08:56 AM
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JonJay JonJay is offline
 
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Quote:
Originally Posted by svyolo View Post
I have a couple of VDO oil pressure transducers on Subaru engines, mounted on the engine, that are almost 20 years old.
VDO - 800 hours, 12 years. First I have heard they are junk. Guess I didn?t need to know..... and will be in no rush to remove them. (Provided by JPI as part of their EDM930 package).

In regard to getting a new advisor, I would rather have one who is over the top than one who misses stuff. You can always do your sanity check here. The safety wire thing is a bit surprising though. Makes one think where he got his ?qualifications?.
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