In the intermediate time of searching for a used instrument cluster to replace my leaky one, has anyone plugged off the oil line to the oil pressure gauge? I don't want to plug it off in the dash - seems like it would be better to use a brass screw-on plug at the fitting where the line comes out of the bottom of the oil filter canister.

I know, I know, there is a very small risk of running my 617 on low oil pressure but this is merely a temporary fix designed to keep me from getting oil on my slacks.

Anyone know what size of a screw-on plug I'd need? I obviously need to have it there before un-doing that fitting.

Cheers.

I know you're probably way ahead of me here, but did you verify that it's the guage that's leaking, and not an oil-fouled vacuum valve on the ignition switch assembly? My 300D ignition switch leaked oil badly when my vacuum pump diaphragm went south...

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- Nate

'85 300SD (200 kmi), Running on Biodiesel
'83 300D (230 kmi, RIP)
'80 300D (150 kmi, Foster Car)

Thanks - it is without a doubt the gauge - I can see it dripping down the back of the cluster when I remove the sound baffle from under the dash, throw my back out laying on my back in the footwell, and peer up at the back of the cluster.

Why not get a female cap end to plug off the line at the guage? Seems like it would be easier than craning down to get at the oil line in the engine compartment.
Often times you will find a better deal getting a whole cluster off eBay than trying to win a oil/fuel/temp guage auction. Junkyards in my experience always show the cluster as one of the first things to get stripped off a car. A new VDO oil/fuel/temp cluster is around $400. Ebay is definitely the way. Otherwise this forum and the MBCA forum should have somebody selling parts that can help you.

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'02 BMW 325i
'85 300D 450k
'93 190E 2.6 170k(killed by tree)
'08 Ducati Hypermotard 1100S 6k
'06 Ducati S2R800 14k(sold)

Personal experience has taught me it is indeed much easier to pop the cluster out a little and pull the line than it is to try to cram in the little space between steering box and filter to get at the likely frozen in fitting (from heat cycling) which wants to round off at the nut and creates a need to remove cover plate on filter housing, heat and remove fitting, then remove melted section of plastic gauge line, try to heat enough to get to slip on fitting and not mush/melt, get new gasket, and try to reassemble.....

What a PITA that turned into... (I was trying to remove the line during prep to remove engine, I pulled the plate, tied it out of the way, pulled engine, then dealt with the repairs) I've had the line off at the gauge with no troubles several times.

there is no reason you cant plug it off temporarily.

i am not discounting the above posts though. they sound valid.

i too would question a leaking guage. i have had 29 benzes, most of them old, and never a guage failure. never a line failure either.

i have left the line unhooked myself before though. and had oil fill my socks. yech!

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

The gages do leak, I've had one and replaced the bourdon tube. You can get a female cap as noted above; you should be able to find one at a good hardware store, one that has the banks of drawers of loose fasteners. You could also plug it at the filter housing, but my experience is that you won't be able to get the fitting out without destroying it. Another possibility is to clamp the line.

I just replaced the line from the engine to the oil pressure gauge. I used a regular flare nut wrench from underneath and it came right off. I could have done it from above with a crowfoot flare nut wrench and a looong extension, but I don't have any of those.

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1984 300TD

on my W116 i cut the line from the bottom of the oil filter and then screwed a woodscrew into the end of the line temporarily stopping the gusher from behind the instrument panel.

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TXBill



Former owner of a few diesel MB cars
1998 Lexus ES 300 In Chicago We Trust