Bent valve cover

quicksandfarmer · Aug 9, 2024

Has anyone experienced a bent valve cover on their inma?

Background: I checked the oil before starting and it was very low. Looking under the hood, there was oil all over the right side of the engine compartment. So I topped it up and started it and looked, and oil was leaking out under the valve cover. I stopped the engine and inspected it closer, and the valve cover gasket had slipped out sideways and oil was leaking out under it. So I loosened the nuts, pushed the gasket back in, tightened the nuts and started it up again, seemed to work.

Then a few days later it slipped out again. Upon closer inspection this time, I noticed that the valve cover was not even with the edge of the engine block, it bulges out in the middle. You can kind of see it in this picture:

So I'm trying to figure out what to do. I've ordered a new gasket to see if that helps. It could be that the cover has always been like that and I never noticed it. But I'm trying to think forward if the bend cover is the problem. Could I bend it back into shape? It's case aluminum about a quarter inch thick. I worry that it will never bend quite into shape and there will always be irregularity that keeps it from sealing.

Or should I try sealing it with liquid gasket? I think that would do a better job of adapting to the irregularity.

Other thoughts?

alexpops · Aug 9, 2024

take it off/clean it up/& see what's going on. Is it deformed like from under excess pressure? like something hit it from inside? or is it a bad casting/press job? from the pic, it looks like you got way more than a gasket issue going on. there's oil all over the valve cover like it's coming from somewhere higher up. you won't be able to tell till you get it clean.

CliffordK · Aug 9, 2024

1/4" thick would be mighty thick aluminum.

Can you tell if the valve cover was cast, or forged/extruded?

If it was cast, it will be tough to do much with it.

If I saw obvious signs of a previous bend (and no cracks), I might try bending it back. However, it might also be a manufacturing defect.

Can you locate a new valve cover?

I like to add a gasket sealant to my gaskets. Yet, I fear this may be a losing battle.

2515R Dude · Aug 9, 2024

Can you clean the cover and post a picture of it?
I highly doubt it is bent for two reasons: 1- If it is a manufacturer's defect, why it did not leak for 17 years you own the tractor?
2. if it is bent indeed, so, it is something recent because you just noticed it, meaning there is a much, much bigger problem.

5030 · Aug 9, 2024

If it's a Jinma, the valve cover is pressed steel btw.

piper184 · Aug 9, 2024

It is perfectly acceptable to use RTV in place of a low pressure gasket. The down side is that it is harder to remove the next time.

BUT, you have to figure out what went wrong before attempting any repairs.

I am not familiar with your particular engine but can definitely tell you that the 284 with the Y85 engine uses a stamped sheet metal cover and a fairly thick and stiff gasket. I had mine off for the valve adjust and the gasket was good enough to re-use. I did however clean it well and give it a very thin coating of high temp RTV (what I had on hand at the time) to aid in sealing.

I would suggest cleaning the exterior of the engine.
Removing the valve cover and gasket and clean them separately.
Inspect bowed out area for anything out of "whack". Think loose rocker or rocker shaft. Perhaps a broken valve spring.
If all is well, do the valve adjust, since it is open anyway
Use a small hammer and gently do some sheet metal work to reshape the cover.
Install with new gasket. Use RTV if you think it is needed.
Let set overnight and do a test run.

Please report back with pictures if possible.

Best of luck

quicksandfarmer · Sep 12, 2024

I had a chance to look at it today. It turns out the valve cover is cracked:

When the bolts are tightened down it flexes along the crack and bulges out.

I have to see if I can get a replacement.

piper184 · Sep 12, 2024

Well, that sucks!

Find the data plate on the engine and have a go at the search engines. Odds are one of the online dealers can help you.

Affordable tractors and Circle G come to the top of my mind, but there are others that are worthy too.

A really good weld shop may be able to fix it for you if you can't find a replacement. Welding dirty, oily cast aluminum of unknown alloy would not be in my wheelhouse to even try. Last resort kind of thing.

Good luck and let us know how it turns out

5030 · Sep 12, 2024

Too big of a crack to TIG. Replace it.

quicksandfarmer · Sep 12, 2024

So far the only site I've found that even has it listed is Circle G, but it's out of stock:

Valve Cover-YD485

Bin 11

www.circlegtractorparts.com

I was hoping they'd have a part number that I could Google but they have the SKU as "Valve Cover-YD485."

AliBaba has this, which is close but not right: