336D injectors

[Car Doc]

Can you air your tester up with shop air?

Reason I say is that will help id whether its rings or valves. The engine needs all the rockers completely removed so the valves wont operate when air is added and the engine spins.

Be carefull when airing them it will spin the engine when the pistons are shoved down by air dont have stuff on the crank bolt or in the belt etc.

Listen to where the air is coming from either the crankcase or intake or exhaust ports.

The head is a piece of cake to R&R btw and the pan and pistons will come out very easily also if you need to re-ring it.

 

[Vern]

Went back and rigged an air hose and put 100 psi. Sounds like it is leaking through the intake valve - the one that head the bent push rod. Pulled the dip stick and could not hear anything from there. I have rebuilt a couple old harley's that even ran when I was done - we will see what happens with the yanmar.

 

[Domush]

I just want to say thanks for posting all of this info online. I have a feeling I need to do the exact same troubleshooting as you are now, so this has all been a monumental help to me.

I feel for you, but I'm very glad you are getting around to doing it now.

 

[Car Doc]

Went back and rigged an air hose and put 100 psi. Sounds like it is leaking through the intake valve - the one that head the bent push rod. Pulled the dip stick and could not hear anything from there. I have rebuilt a couple old harley's that even ran when I was done - we will see what happens with the yanmar.

That's about what I figured from the start.

I have another tip for you-when you get the head sitting on a bench take and spray some dawn soapy water around all the valve seats and then blow air into the ports up close to the valves as you can look at the bubbles. I am curious about #1 cyl I hope its got one not seating also.

Take pics if you dont mind for these other guys? :thumbsup:

 

[grainger12002]

looks like you are onto something, looks like the push rod was falling off for a reason....maybe as simple as a stuck valve from sitting. It will be up and running soon by the sounds of things...keep us posted

Lloyd

 

[Car Doc]

I have a couple pics of mine to share when I did my valve job etc.

The last pic where I painted I am indicating the areas my gasket was leaking combustion into the cooling system.

 

[Vern]

Thanks for all the help. I have to help move someone tomorrow but plan on digging in on Sunday.

Thanks again

 

[Vern]

Pulled the head today - first thing I found was when the exhaust manifold was removed the port was over 1/2 plugged with carbon build up. The head came off pretty easy no big issues, I did not see anything on the head gasket indicating it was leaking. The middle cylinder has some carbon build up on the top of the piston but the bore is smooth.
Put air to the head and could see a lot of bubbles from around the exhaust valve, some in the front cylinder and even a few in the rear.
Should I pull the lifters before I take it in?

Thanks

Vern

 

[Domush]

If the valve just needs lapping, why not just lap it yourself?

Is there more to the process that I don't know?

Also, what did you have to remove to get the head off? I notice the entire top of the block is removed. Did you do that as a "might as well check the rings and cylinders" step or is that necessary?

 

[Vern]

Domush - That is the head. I am not as familiar with diesel engines but I have had gas that the valve seats are bad and need to be replaced. I am going to take it into a machine shop I use and have them go tthrough it - Do not want to have to take it off again.
Will let you know what they find.

Vern