1520 Engine hard start and smoking

bbomer · Apr 1, 2010

Have you ever checked your valve adjustment.

I'm not sure exactly what that means. How would I go about doing that?
The only thing I can find in the service manual is "Spill-Timing" and I don't have the required tools for that...

Thanks for all the reply's, it's always nice to get advice from people who know.

sld · Apr 2, 2010

While I have never done it, it appears that the manual says to check the valve clearance while the engine is running (valve cover removed). The specified clearance for mine is .008.

What I could never visualize is how to take this measurement while the engine is running. It seems that the feeler gauge would be hit or miss and the oil would be going everywhere.

Hopefully someone that has done this can offer some advice.

jinman · Apr 3, 2010

My Repair Manual for my tractor says to make the adjustment with the engine cold/not running. Ensure the piston is at TDC of the compression stroke where both intake and exhaust valves are closed and the tappet is fully retracted. Adjust the tappet gap for 0.008" on both intake and exhaust.

Ensuring the piston is at TDC might be the hardest thing since you can't see the cam and you'd probably have to remove the injector to feel/see the piston rise to TDC. You might be able to do it through the glowplug ports too.

I think before doing much disassembly to perform a valve lash adjustment, I'd want to run a compression test to see what the overall condition of the cylinders and head are. My tractor manual says to hook up a compression gage in the glow plug holes and measure compression. If the OP is checking/changing glowplugs, that might also be something he can do. The compression specs for my tractor call for the engine to be rotating at 200 rpm which is the speed the starter spins the engine. A pressure test gage and fittings might be a bit expensive for a one-time use. That would probably be best to have done at a dealer's service dept. as well as any valve adjustment if you don't know what you are doing (like me...

). Getting valve lash too tight and having a valve snap off and get sucked into the engine is a sure recipe for disaster. I wouldn't take the chance. Just me. . . .

bbomer · Apr 4, 2010

I came to the same conclusion as jinman. It's scheduled to go to the dealer to check compression and timing.

RickB · Apr 4, 2010

bbomer said:
I came to the same conclusion as jinman. It's scheduled to go to the dealer to check compression and timing.

A waste of money if they do that before checking the glowplugs. If it runs well warmed up, compression and timing aren't likely the problem. Symptoms from those problems don't go away at operating temperature. But you seem content to toss good money after bad, and it's your dime.

jinman · Apr 4, 2010

RickB said:
A waste of money if they do that before checking the glowplugs. If it runs well warmed up, compression and timing aren't likely the problem. Symptoms from those problems don't go away at operating temperature. But you seem content to toss good money after bad, and it's your dime.

I agree completely. If you find bad glowplugs and remove them, doing a compression check is something you might do at that time if you have a compression gage available. Checking glowplugs and verifying their condition is the first step. BBomer, please don't confuse what I said as a possibility as the most likely problem. Check the easy/most likely stuff first.

bbomer · Apr 5, 2010

If it runs well warmed up, compression and timing aren't likely the problem.

As I mentioned in an earlier post, it still smokes/misses at high RPM regardless of temp. So I guess I could say that it doesn't actually run that well, though better than cold.

It is going in to the shop more for the gurgling/boiling coolant issue than the starting/smoking issue (may be related). I simply don't have the experience or enough hours in the day (especially now that spring is upon us) to diagnose and fix everything.

However, I will test the glowplugs myself before it goes in. I know for sure that at least some or all of them are at least partially working because it won't start at all if I don't warm them.

AndyG · Apr 7, 2010

bbomer said:
It is going in to the shop more for the gurgling/boiling coolant issue than the starting/smoking issue (may be related). I simply don't have the experience or enough hours in the day (especially now that spring is upon us) to diagnose and fix everything.
.

That's a pretty important little detail that you left out. I originally thought that you were experiencing a fuel flow restriction. The gurgling coolant coupled with the rough running that you mentioned points a finger at a blown head gasket.

RickB · Apr 7, 2010

AndyG said:
That's a pretty important little detail that you left out. I originally thought that you were experiencing a fuel flow restriction. The gurgling coolant coupled with the rough running that you mentioned points a finger at a blown head gasket.

It's annoying when folks come here for advise, give you half the symptoms, then quibble about a response to something they originally claimed no knowledge about. Small wonder guys tire of this and move on.........