As far as I know, and the Bentley confirms that the 85, like the 83.5-84 (which I have), only has one sensor -- the one on the side, which is a .3bar, the low pressure sender. They didn't go to two sensors until the Digifiant, in 86. That makes this particularly interesting. They typically go off at low idle after running hot for a bit. The oil is thinnest, the pressure lowest, and the switch goes off and flickers the light. Does the automatic drop to idle when going downhill? At any rate, hooking up a pressure gauge will tell all. I just went through installing one (permanently) while also modifying an 89-90 dash to work with my 1.9(re-wire plus disabling the >2000 rpm pressure input). With no high pressure switch on the digijet models, the gauge is nice to have. Rich < This is critical to diagnose immediately. It is possible that the high pressure sensor is bad. It is however possible that the oil pressure is low for the high pressure sender which is indicating worn rod bearings and if that's the case the next thing that happens is the number three rod will come out of the case right on top with a loud bang. The only true way to know what's going on is to connect up a real oil pressure gauge to the port between the push rod tubes and get a true oil pressure reading of the oil when hot at running temperatures. PITA I know but unless you want to see that number three rod in your engine compartment it's the only right way. This is why it is highly recommended to have a "REAL" oil pressure gauge mounted on the dash board, instead of a bobble head, to keep an eye on the "REAL" oil pressure of these old high mileage waterboxer engines > |
Please note - During the past 17 years of operation, several gigabytes of
Vanagon mail messages have been archived. Searching the entire collection
will take up to five minutes to complete. Please be patient!
Return to the archives @ gerry.vanagon.com
The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.
Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.