adjusted valves = hard to start - Page 2 - PeachParts Mercedes-Benz Forum

79Mercy · #1 01-23-2011, 11:23 PM

Quote:

Originally Posted by pawoSD

I second this. Who knows how much nasty gunk is in that poor engine if this type of stuff is being run through it. The rings and valves are probably coated with the stuff.

This also supports my idea in post #5

bustedbenz · #2 01-23-2011, 08:35 PM

The glow plug fuse is only 80 amps, thus the questioning post. It is indeed a fuse; we weren't doubting its existence. Just your rating.

funola · #3 01-23-2011, 11:37 PM

Check the fuel shutoff lever bracket that it is not flipped in the wrong position when you put the valve cover on.

supercub · #4 01-24-2011, 09:15 AM

A slight drag is good, you can go up .001", and if it does not slide in, you know that you are not over.

supercub · #5 01-24-2011, 09:16 AM

Is the hose on top of the air filter the way it should be?

vstech · #6 01-24-2011, 09:30 AM

ya. the strip is usually rated at 80 amps, and it is VERY common to fail. preventing voltage from reaching the glow plugs.

angst · #7 01-24-2011, 12:45 PM

Update.
Power to all plugs.
Furthest back plug would not glow when pulled out and hooked to jumper cables. I replaced it with one that I just pulled out of one of the middle cylinders for testing. I may have broken it when installing it in the back cylinder though. The top part of the body with the electric threads can spin around when you are trying to tighten the nut.
Have only been able to check one other plug. The one in the center which was fine. Went to pull the one furthest to the front and it is suffering the same fate of having the top part of the body is spinning and not allowing me to take the nut off.

I did find one thing unplugged. It was a single wire electrical plug that goes into the main body of the engine in the neighborhood of the middle glow plug.

Went to start and it did start but not convincingly strongly despite it being 48f and only 35f last night.
I am going to keep digging into more plugs but am probably going to have to just start it up and go about my errands shortly and any valve re-checking would have to be tomorrow.
I may try to shop for a battery. Could be a factor. 590 amps when tested on the car at Advance Auto. Any thoughts on that?

Quote:

Check the fuel shutoff lever bracket that it is not flipped in the wrong position when you put the valve cover on

Been there done that before. Fortunately didn't have everything bolted down before I realized.

Quote:

Is the hose on top of the air filter the way it should be

the vapor recovery hose? Its fine.
All of the EGR related hoses mysteriously vanished long ago.

Quote:

A slight drag is good, you can go up .001", and if it does not slide in, you know that you are not over.

Sweet tip. Thanks.

Edit: another update.
After starting the yellow dash light between the brake and battery light lights up. That is usually the brake wear indicator light but I could def. see the wires having been switched somewhere along the way.
Battery reads
12.43v engine off
14.5v idle

Walkenvol · #8 01-24-2011, 03:17 PM

If I'm following you correctly, the car runs well a few minutes after starting? Can we assume you pulled the glow plugs in order to release the compression while rotating the cam? Seems like it would have to be a glow plug issue. Take all 5 out. Bench test them. Replace the defective ones. Don't over tighten the nuts that hold the wires on the GP's. See if this solves your cold start problem.

As for the expected increased performance, unless the valves were considerably out of adjustment a huge performance increase should not be expected.

Good Luck!

angst · #9 01-24-2011, 03:52 PM

Quote:

If I'm following you correctly, the car runs well a few minutes after starting?

Yes. Runs fine, but hard time starting. Starts fine after warm.

Quote:

Can we assume you pulled the glow plugs in order to release the compression while rotating the cam?

oops. No. Only minor rotation was needed to line up each next one. Is that a problem?

Quote:

Seems like it would have to be a glow plug issue. Take all 5 out. Bench test them. Replace the defective ones. Don't over tighten the nuts that hold the wires on the GP's. See if this solves your cold start problem.

Will continue to test the plugs out of the car later this evening. I guess the one that got overtightened will come out too.

Quote:

As for the expected increased performance, unless the valves were considerably out of adjustment a huge performance increase should not be expected.

sounds reasonable. It was running ok. I was just looking for a little better cold starts. It had been about 18k since last valve job.

angst · #10 01-27-2011, 08:09 PM

Bump with another update.
Through this week i finished fiddling with the glow plugs and have removed each and confirmed it glowing hot with jumper cables and a battery.
The battery has been on a de-sulphator all week.
I think I can safely eliminate electrical as the source of the lousy starts.

Tomorrow I am pulling the valve cover and going at the valve adjustment again. My thoughts are to work off the suggestion of after adjusting trying one feeler gauge bigger and seeing if it fits in.
I was going to take that idea a step further and actually adjust for one step down from the .35 and .1 gauges and then insert the proper .35 and .1 gauges to see how they feel.

vstech · #11 01-27-2011, 08:36 PM

you might want to flush out the PC's while the glows are out.
spray some PB blaster in the holes, and let it soak for a bit,, then spin the motor over really well, to flush out any liquid you'll be amazed at the crud that sprays out of that motor.

leathermang · #12 01-30-2011, 11:58 AM

Quote:

Originally Posted by vstech

you might want to flush out the PC's while the glows are out.
spray some PB blaster in the holes, and let it soak for a bit,, then spin the motor over really well, to flush out any liquid you'll be amazed at the crud that sprays out of that motor.

What happens when that cylinder sucks first ?
It draws that into Where ? and how much trouble is it to get it out THEN ?

LOL

josha37 · #13 01-30-2011, 11:55 AM

You have to make the distinction between not cranking fast enough and not burning well enough or enough to fire before decissions like that can be made.

layback40 · #14 01-30-2011, 01:23 PM

Has a compression test been done on the motor?

layback40 · #15 01-31-2011, 12:07 AM

If your battery is bad, you will get one glow & about ten seconds of cranking before it dies & needs a recharge. The fact that it runs so rough when it starts cold suggests the problem may not be the battery. How much blow by does it have?
My thoughts are you have stuck rings on at least one cylinder. A compression test will show what is going on.

I suggested stuck rings 24 posts ago. Having seen this chain of events so many times.
Bad starting when cold
GP's good
Valves adjusted
Starts ok when warm

This is a text book case of low compression from stuck rings. If not, I want to know what is causing it !!