336D injectors
- Thread starter Vern
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284 - The push rod was bent, can't tell from what. The tractor looks like it sat neglected for a long period so am guessing a stuck valve. I straightened the push rod using a straight edge until I can get one ordered.
I have a lather and figured I could turn a compression tester down but will have to check my gage to see if it will go high enough.
Can the injector pump be rebuilt? I took my injecters to a commercial diesel company but Yanmar would not sell them the parts or new injectors, told them it would have to be from an ag shop. This company did Yanmar boat engines.
Thanks again
I have a lather and figured I could turn a compression tester down but will have to check my gage to see if it will go high enough.
Can the injector pump be rebuilt? I took my injecters to a commercial diesel company but Yanmar would not sell them the parts or new injectors, told them it would have to be from an ag shop. This company did Yanmar boat engines.
Thanks again
Welcome Vern, IMHO the compression test is the most important thing you need to know at this point in time! It will never run right with a cyl down even a little bit no matter how many new parts you throw at it.
Oh yeah it can be rebuilt JD has been using these engines forever any decent pump shop should be able to do it but I would have them test it first.
btw I dont throw parts at anything or recommend it I test test test and once I can prove it bad it gets replaced fwtw.
You could have had your injectors pop tested before replacing them but thats hind sight. I saw where you had already ordered them it was too late to mention it.
Any gage that is made for gas will work and a grease gun hose is 1/4p and is high pressure rated so a gage a coupler a hose and your adapter is all you need to build a compression gage. good luck
Picked this up at Harbor Freight today - 29.95, I do not like buying there but what little I will use this figured it would be fine.
Drilled and threaded a pc of 1 1/4 round stock, its a couple .100 smaller than the injector so turned a small shoulder to fit into the insulation washer to keep it centered. Raining here yet so will try it out tomorrow.
Drilled and threaded a pc of 1 1/4 round stock, its a couple .100 smaller than the injector so turned a small shoulder to fit into the insulation washer to keep it centered. Raining here yet so will try it out tomorrow.
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California
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I bought the HF diesel compression test kit with the fewest adapters. I thought I would tap the top of a junk injector to put in a 1/4" fitting, to make an adapter. (It would also need its internals removed). Has anyone done this?
Man thats an awesome idea! Between Vern and his lathe skills and this injector idea you guys have the Yanmar compression test made easy! :thumbsup:
So I finally got a break in the weather and work and did a compression test. Happy to say the rig worked like someone knew what they were doing.
Front - 360
Middle - 260
Rear - 400
While pressure testing the middle cylinder blew out the bottom ring that holds the insulation seal - it had a layer of oil on the bottom where the rear had carbon build up.
Looks like I am pulling the head - any thing to watch out for?
thanks
Vern
Front - 360
Middle - 260
Rear - 400
While pressure testing the middle cylinder blew out the bottom ring that holds the insulation seal - it had a layer of oil on the bottom where the rear had carbon build up.
Looks like I am pulling the head - any thing to watch out for?
thanks
Vern
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.
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.
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.
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Domush
Platinum Member
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.
I feel for you, but I'm very glad you are getting around to doing it now.
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
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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
Lloyd
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
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
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Domush
Platinum Member
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?
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?
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
Will let you know what they find.
Vern
