Head gasket replacement - how to?

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agirlandhertractor
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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Mon Aug 21, 2017 9:14 pm

Mayhaps so, I ended up having a local welding shop tack a nut on. Still required a LOT of heat to break free. Ordered a set of new M8 x 1.25 x 35mm studs (regular steel, not stainless) to replace later on.

Uploading new pics, will post up shortly.

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Mon Aug 21, 2017 9:20 pm

Next up is the rocker arm, shown here with related components:

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Before attaching the rocker arm assembly, install the valve protector caps on the tops of each valve. There is only one type of cap so don't worry about mixing & matching with intake & exhaust valvues.

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Next, install the six pushrods into the block. Careful that they don't fall in the block. They rest in a little cup at the bottom of each pocket:
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Now install the rocker arm assembly. You can line up each pushrod after placing the rocker arm assembly. I thought lining them up might be aggravating but it was very easy to do.
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Next, install and tighten the cylinder head assist bolts to 22 ft-lbs. The rocker arm assembly nuts are tightened to 40 ft-lbs.
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Last edited by agirlandhertractor on Tue Aug 22, 2017 9:25 am, edited 3 times in total.

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Mon Aug 21, 2017 9:32 pm

Valve Adjustment

Now is an ideal time to check and set valve lash. You'll need a flat screwdriver, 13mm box end wrench, and a feeler gauge (.006 in).
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Intake and exhaust are both set to .006 in (manual calls for .006 - .008 in fwiw). If you've never set valves take your time, tightening the nut may cause the lash to tighten up a bit, so be sure to double check and reset as needed (backing off the set screw slightly before tightening if needed). You want a slight pull or drag on the feeler gauge - not too tight or not too loose.
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Last edited by agirlandhertractor on Tue Aug 22, 2017 9:26 am, edited 2 times in total.

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Tue Aug 22, 2017 9:24 am

Got the rocker arm cover installed with additional orange RTV with the new rubber o-ring gasket. Spread it thin but obviously thinned it little further than the cover sits. I've always had trouble getting the valve cover gasket to seal properly. Tried a new o-ring by itself (with thoroughly cleaned surfaces), no dice. Last time I used black permetex and that worked a little better but still had a little seepage. We'll see how the orange does.

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Next I installed the air manifold that sits on the intake side of the head. The new rubber gasket was a bit fidgety but finally got it lined up and torqued down. The old rubber gasket did not have sealant so I am using just the bare gasket here.

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Got the broken stud removed. Plan to replace rest with new M8 x 1.25 x 35mm studs in the future. Better grab the others while I still have enough shaft to use a stud remove on.

Also, the PO set a new gasket on top of an old gasket. Took a while to scrape the original off and get the surface clean.
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Muffler flange all cleaned up.
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Got the water pump housing, new water pump, and new lower radiator hose (with new clamps) installed:
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Next up, reinstalling the fuel lines. Calling it a night for now though.

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Tue Aug 22, 2017 9:55 pm

reserved for pics

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Tue Aug 22, 2017 9:59 pm

It lives! Got the injector lines installed and bled and it's running like a top again.
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My little tractor decided I needed to be bled, too!
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Tomorrow I have to put the radiator shroud on and also flush the coolant system completely. Not sure how best to go about that, will search the board...

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Re: Head gasket replacement - how to?

Postby Crump » Thu Aug 24, 2017 11:08 pm

Thanks for this, just doing mine today (again),and its been a big help. What method did you use to clean the block surface without getting all the gasket material down the coolant passages, bolt holes etc... Thanks.

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Fri Aug 25, 2017 5:22 am

I used a straight razor to very carefully remove the old gasket material. Also used a shop vacuum to pull away any loose bits.

I cleaned the head after initial scaping with solvent and then again with purple power (sprayed onto a clean rag). Went over it after that once more with the razor. Take care not to gouge either surface with the razor.

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Sat Aug 26, 2017 1:13 pm

My baby is running again, smooth as can be. The valve adjustment did wonders for ease of starting.

Today I flushed the coolant since that was the last thing that needed to be done. I ran a little powder Cascade, flushed with water, then ran a little Simple Green and flushed that with water. Proceeded to fill and flush 5 times to ensure all of the soap/acidic residue was gone.

I then topped off the system with Cat ELC (Extended Life Coolant). It's not toxic to pets like regular antifreeze. Plus, if it is good enough for my Powerstroke 7.3 diesel, and for Caterpillar D11 dozers it is good enough for my Yanmar.

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The fan cowling can be installed by removing the four 13mm bolts holding the radiator frame on, and then removing the top hose. It will rock forward just enough to slide in.

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Make sure you leave enough clearance for the cowling to fit above the lower radiator hose & clamp. I had to rotate my clamp down a bit.
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beartrace
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Re: Head gasket replacement - how to?

Postby beartrace » Sun Aug 27, 2017 11:21 am

agirlandhertractor _ Great tech article with photos. Question, I am replacing my head, reassembling. I placed the valve assembly on the bolts, place cups on the valve stems, and line up the pushrods - the rocker arms do not fit close on the valve stems. There is up to a 3/8" gap on some valves, others fit ok. This project has taken some time due to other things. I reinstalled 3 x to make sure that there is no other impediment.
Questions:
1. In the interim could the engine have rotated out of the original position? I did not rotate the crank.
2. Is this normal and will it resolve itself when adjusting for lash?
3. ???

Thanks in advance.

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Sun Aug 27, 2017 11:39 am

On my 1601 the camshaft is located in the block so you can rotate the crank without affecting head reassembly. If you take out the cam for whatever reason then you have to re-time it all.

Are you working on a 1601, or what model do you have?

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Re: Head gasket replacement - how to?

Postby beartrace » Sun Aug 27, 2017 11:47 am

I am a dork. Just needed to torque down the rocker assembly. Cannot believe such a small height make such a big difference!

winston
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Re: Head gasket replacement - how to?

Postby winston » Sun Aug 27, 2017 1:13 pm

Butting in here as usual. If you did not loosen any of your rocker arms off during the disassembly process and have just set the rocker arms back on untouched then there is no way you should have 3/8" gap on any valve. Are you confident your pushrods are all sitting on the lifters as shown here? Parts drawing calling them tappets, I call them lifters.
http://www.hoyetractor.com/CTGY/YM1600CAM.htm

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Re: Head gasket replacement - how to?

Postby agirlandhertractor » Sun Aug 27, 2017 10:27 pm

There are pictures at the top of this thread page showing how the lifters fit into the block and on the rocker arm. May be that one of the lifters wasn't seated fully and that caused the gap. Sounds like he has it worked out now regardless! :)

winston
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Re: Head gasket replacement - how to?

Postby winston » Mon Aug 28, 2017 4:48 am

agirlandhertractor wrote:There are pictures at the top of this thread page showing how the lifters fit into the block and on the rocker arm. May be that one of the lifters wasn't seated fully and that caused the gap. Sounds like he has it worked out now regardless! :)


Yes, I don't think I read beartrace's last post close enough. When he torqued down he opened some of the valves and at the same time closed the 3/8" gap on other valves. Thanks to you agirlandhertractor for taking the time with all the pictures and detaii. This will help others down the way.


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