VO conversion - engine failure - Page 3 - PeachParts Mercedes-Benz Forum

funola · #31 11-07-2005, 06:56 PM

Mike, if you can prove that AAA used starting fluid to start your diesel engine and ruined it in the process, maybe you can get a new engine out of the deal?

I am making a glow plug compression tester. See pics. It is not finished yet but will be in a few days. I have to add a schrader valve to the glow plug adapter tip, get a flare fitting and adapter to mate up to the 0-1000 psi gauge then I'm done. To use, take the glow plug out, screw in the glow plug adapter, screw in the gauge with the copper pipe with a flare fitting and crank away. Would people be interested in my compression tester in the tool rental program?

Quote:

Originally Posted by Mike Hauser

kip, interesting observation. Before the engine stopped running AAA started it once with starting fluid and the noises the engine made were probably the kick-back you are referring to. I have no plans to try starting fluid again at this point.

Tony, I will try the oil should I find low compression. Would that be regular engine oil? And how much is a good amount.

The issue I am having now is that I discovered that nobody has a compression tester for a diesel or they don't have an adapter for a Mercedes or both. I found one on Toolsource.com but the Mercedes adapter is backordered and only expected to come in mid-December.

Does anybody have a good source for a compression tester (including the correct adapter)? I would prefer the adapter for the glow plugs since they seem generally easier to remove than the injectors. That one seems more difficult to find than the injector adapter.

But just in case I have to pull the injectors, what is a good way to get the injectors out? I saw that Samstag Sales sells a special socket to remove the injectors (it has cut-outs for the leak line pipes). Is that necessary or advisable or can an injector be pulled safely with something like a crow foot?

lietuviai · #32 11-07-2005, 07:48 PM

Your compression tester looks like a neat thing even simple enough to duplicate. It looks like it'd easily work on the older engines. It would be tough to use on the later engines, like the 603, where the glow plugs are nearly impossible to reach w/o taking off the intake manifold.

kip Foss · #33 11-07-2005, 08:39 PM

Mike.

You can get a Diesel compression tester with all the common adaptors from Harbor Freight for less than $150. You can get an old glow plug, cut it off just above the threads, thread it to accept either a 3/8 in. npt pipe thread or braze on a hydraulic hose adaptor and put the gauge on the end of the hose. Add a 500 or 1,000 psi gauge and Bob's your uncle.

You can use starting fluid on a Diesel as long as you don't operate the glow plugs.

#34 11-08-2005, 12:56 AM

If your glowplugs are one of the off brands...be very suspicuous.

Brand new autolites in my car before I got it failed after only a few starts.

The starting fluid should have made your engine sound very bad...it should have kicked and bucked and maybe even screamed (a factory installed option)

lietuviai · #35 11-08-2005, 11:04 AM

Even with bad glow plugs, the car should have started unless it was really cold that day. Even if it didn't start, the car would have coughed some smoke out the tailpipe.
If the compression was bad the engine would have turned over very easy. It certainly sounds like a fuel delivery problem. Years ago I worked on a Mitsubishi turbo diesel with bad compression. It would still try to start but it wouldn't run. It belched smoke out the tailpipe from the incomplete combustion. It turned over fairly easy as well. I tried swapping in one of those used engines from Japan but it turned out no better. I gave up and ended up getting rid of it.

Mike Hauser · #36 11-08-2005, 11:31 AM

A compression tester is on order and should be here in a few days. I got the injector type because the glow plug adapter was ridiculously backordered. Anything I should look out for that I don't break anything? The manual calls for a sealing ring to be replaced with a new one when re-installing the injectors. Is this something I can get away with if I don't do it and perhaps do it once it runs again or am I asking for trouble?

More to come on this one hopefully by the weekend.

lietuviai · #37 11-08-2005, 01:32 PM

Not really but they're fairly cheap so it's not a bad idea to replace them.

coelcanth · #38 11-08-2005, 11:08 PM

you must replace the heat shields (crush washers) every time you remove the injectors

see this thread for more info:
http://www.peachparts.com/shopforum/showthread.php?t=93265&highlight=injector+crush+washers

Mike Hauser · #39 11-09-2005, 09:49 AM

Thanks for the thread coelcanth, very informative.

BruceMcC · #40 11-09-2005, 11:25 AM

Two things come to mind from your description, Mike.

First, if you loosen the delivery line at the injector and crank, you should see fuel leaking out there. I'd confirm this at all injectors. That would tell you whether the IP is functioning at least somewhat.

The other thing that concerned me from your description is the leaking new clear plastic fuel lines. Air is the enemy of IPs. Anyplace that leaks is also an air entry point. Whether the bubbles are small or large, until the air is bled out I wouldn't expect the engine to start. That can take lots of cranking (with the injector lines loosened first).

A resistance check on the glow plugs from the unplugged harness connector at the GP relay would be a good idea, also. I think it was 0.6 ohms but don't recall.

Best Wishes,
Bruce McCreary
Snowflake, AZ (6000 ft elevation, yes it snows)
'85 300D 170K

1983/300CD · #41 11-09-2005, 12:49 PM

When I read "clear fuel lines" I thought "Uh-oh". Everything I have ever read about diesels warn against using the clear ones. Something about needing to be rated for diesel fuel. Little bubbles turn into big bubbles in places. If you're having problems running diesel, but not VO, then it might be your diesel lines (diesel half of the system, not what they share).

BTW, my 617 primer pump sends the air back to the tank via the fuel return line, so cracking lines is not necessary.

boneheaddoctor · #42 11-09-2005, 12:53 PM

Quote:

Originally Posted by 1983/300CD

When I read "clear fuel lines" I thought "Uh-oh". Everything I have ever read about diesels warn against using the clear ones. Something about needing to be rated for diesel fuel. Little bubbles turn into big bubbles in places. If you're having problems running diesel, but not VO, then it might be your diesel lines (diesel half of the system, not what they share).

BTW, my 617 primer pump sends the air back to the tank via the fuel return line, so cracking lines is not necessary.

I assume the clear lines to be the three lines between the lift pump and the Engine..the two directly to the IP and the one from the lift to the filter.

When new those are clear..when old they are brown. On the OM617 anyway...

1983/300CD · #43 11-09-2005, 12:59 PM

Maybe I was reading posts from a madman then.

chocolatesoup · #44 11-13-2005, 09:58 PM

Quote:

Originally Posted by Mike Hauser

I have posted a while ago that my car, an 84 300SD with a VO conversion kit would no longer start (the thread was lost in the hard drive crash last month). I tried a few things that I will post later but was unsuccessful in my attempts. I'm getting to the point that I want to know what killed my car. If it can be fixed along the way that's a bonus.

Mike did yours no longer start after dieing when you switched to wvo. mine did and now i cant get it started. and couldnt get it started while engine was still hot from running. What do i do?

here is my story.

ive just installed a 2 tank wvo
system in my 81 300d. it was running off both tanks with diesel in
both the tanks so i know its all hooked up and will run off both
tanks. I started adding veggie to the 2nd tank that had some diesel in
it. so it maybe has a mix of 20% diesel 80% wvo. i was testing my
system out. warmed up the car and flipped it over to the 2nd tank
shortly later it lossed some power and i went back to the diesel tank
and it gained its power back. i tried it again later while cruising in
a parking lot and it lost power and i couldnt switch back to diesel in
time and it shut down. I could not restart the car off of the diesel tank. i vaccum pumped out the fuel in the line from the selector valve to the IP. Then i re primed the line with diesel and could hear it squirting into the IP.
still wouldnt start.

trying to figure out what the problem is, or how to just get it running off of my diesel tank.

I saw BHANSONS post i think may try that, check my lines. i have one question though as how to check for blocked lines. do i disconnect the return line and try to start the car and see if anything comes out?

TonyFrom... thinks i have air in my veggie side, this may be very true. but i was able to get it up and running on diesel before if konked out. so its on my diesel line and that side seems fine. would that effect me being able to restart my car

Mike Hauser · #45 11-16-2005, 11:50 AM

1983/300CD,
the clear lines I have installed are PVC lines. Not at all the first choice to run the car on but I figured that for a short time they should be able to withstand the diesel fuel and not harden. Perhaps that's not a valid assumption. I will get some of the real stuff to install.

I also got finally got the adapter for the compression tester yesterday and will test the compression when I get to it (over the weekend?).

chocolatesoup,
My car would always run better on VO than on diesel. The problems first started to show themselves on diesel, then later also on VO. It's entirely possible that I have an air leak somewhere that worsened gradually over time. The question is: where? Since your conversion is fairly recent something like an air leak is the most likely. It looks like your problem is on the VO side but could also be in the fuel lines the two systems have in common. A leak that's not an issue on diesel could be a big problem on VO due to the difference in viscosity and temperature.