Trouble Removing Injectors On Yanmar 3GM

[lifeofreilly]

I have a Yanmar 3gm and am having trouble removing the injectors. I have gone through the manual and done the prescibed removal steps but the injectors wont budge. The engine is in a C&C 38 so the compartment is tight, I don't want to remove the head if I don't have to. I've rebuilt other diesels before and not had this tough a time getting the injectors out. Any suggestions?

[never monday]

PB Blaster
try turning them back and forth

get the special puller tool from Yanmar

[jpemb7]

I'm not familiar with your engine. But if the injectors are screwed into the head and won't budge, some penetrating fluid ( leave it for a week, patience!) and a bigger lever ( if there is room) on your wrench should do it. If the injectors are clamped, you could try loosening everything off (not completely) and turning the engine over. The compression will usually blow them out. I have used this technique successfully to remove the injectors and the head off my old Volvo on a couple of occasions.. It's pretty dramatic. Just loosen things a bit and start your engine.

Good luck

Jim

[Chief Engineer]

Go with the PB Blaster and patience.

Sometimes a little water gets in betwen the injector and the hole....there is a little rbber o-ring that allegedly prevents that but they tend to "disappear" over the years.

When re-installing, a little anti-seize should be applied....don't glom it all up.....just a little bit.

[lifeofreilly]

Thanks for the suggestions, I have looked up the special puller and already have PB Blaster soaking into the injector bores. Never Seize is an invaluable soft tool on anything that runs in salt water.

[nikki-m]

When we had to remove the injectors on our diesel engines (I can't remember the make - but they were big, noisey red ones, if that helps) we couldn't get enough grip on them to pull them out after unscrewing them, as they were being held in by the rubber seals, and there actually wasn't that much to actually get hold of.
So we used a spare injector pipe - the bit with the nut on which would normally screw down onto the injector - and fastened that onto each injector in turn, and then pulled and heaved on that. It supplied sufficient grip to allow us to pull them out with barely more than grazed nuckles and a few choice words.
Notice the use of "we" here. As we are a team, the engineer did the work whilst I observed!!
Nikki

[Shoalcove]

Be careful with the PB Blaster! I've read (too late unfortunatly...) that it can damage any seals it gets on. It's great stuff just be careful where you aim it.

[Davey1000]

Originally Posted by lifeofreilly

I have a Yanmar 3gm and am having trouble removing the injectors. I have gone through the manual and done the prescibed removal steps but the injectors wont budge. The engine is in a C&C 38 so the compartment is tight, I don't want to remove the head if I don't have to. I've rebuilt other diesels before and not had this tough a time getting the injectors out. Any suggestions?

On Yanmar 1GM, 2GM and 3GM after removing the clamping plate remove the leak-off banjo union on the top of the injector. The thread is M8 ISO which is very common. If you can get some M8 allthread and a heavy piece of steel with an M8 or M8.5 hole down the centre you can improvise a slide hammer. Another way is to fabricate an injector puller using scaffold pipe or similar. Injectors which are rusted-in will need tremendous amounts of force to pull them. In such cases it may be worth using an "Unbrako" pulling bolt rated at 10.9 or higher. The ideal method would be to jack the injectors out using a Hydra Capsule (a hollow hydraulic ram) but the cost of British made versions is rather high (Hollow Ram Jacks - Hydra-Capsule Limited) It might be possible to adapt a scrap car disc brake cylinder to do the same job. The type that has a handbrake actuator built in might be the easiest to modify. Good luck.

[bobconnie]

AHHH look at the ball joint removal tools sold by serveral tool companys snap on to name one find one small enough to fit the base of your injector, tap the right spot on the tool and it will pop right out! just a thought, and ya might try ATF as a un freazer in sted of that expensive stuff it works wonders and is easy to find most everywhere!

[rbyham]

Reviving an older thread here with current problem. Yanmar 3qm30. Bad head gasket necessitated removal of head which I sent to machine shop with injectors in. Found head deck out .003 so shop recommending grind/cut the head. This required removal of injectors and pre-combustion chamber. But machine shop could not get injectors to budge. Even tried a puller after screwing an M8 into top of injector where return line connects. Broke the puller! Even tried carefully heating head. No luck.

At an impasse and considering just grinding valves and not risking head or injectors any more. Engine ran fine once started previously. Assume the bad head gasket made for hard starting but once running had no problems with injectors. So considering just change head gasket and leave the rest go. Doubt the .003 will be a problem with proper torquing.

Any other ideas to get injectors out or thoughts on just leaving them alone? I have located new injectors at $380 for the set of 3. So could unscrew injector body and thread something into nipple that we could get a heavier puller on but afraid toe damage block which would be very high dollar if I could even locate one.

Did not expect this. Old head gasket shows clear blowout on cylinder 3 so thought to clean up head would be the way to go and have the whole top end perfect. Oh well...

[ggray]

I had an injector or two that were hard to get out. I'm pretty sure this was the job I bought a slugging wrench to loosen them with.

[shakey doug]

3 thou is the best part of a fair bit when talking Head to deck trueness. With carbon & corrosion locked injectors you need to be very cruel do not hold back. Clean around Head to injector area, soak with a good penetrene liquid, use a 5lb maul & heavy brass Drift on the solid part of the injector body avoiding the Hp fuel line area. After each session wriggle inj body back & forth trying not to undo the nozzle holder section. I reckon for $ 380 you only get the nozzle & pintle set not the whole box & dice. Remember HIT IT LIKE YOU HATE IT !!

[rbyham]

Thanks folks. So the old leave it alone and hope for the best is not preferred? :-) Terrified to hit like I hate it. Will check on price for new. You may be correct that is just the nozzle...

[boatbod]

Too late now, but usually we remove the injectors before removing the head. The process is to undo the retaining hardware almost all the way, then crank the engine over and hope the compression breaks them loose.

[rbyham]

Well just to close the loop on this one. I took the head back with grouond valves but no cutting of the deck. Never did get injectors out. Put head on and torqued to spec. Got everythin on in about 3 hours and after valve adjust went for start up. It actually scared me because it caught immediately on key turn. Never did that before. Only problem was 3 cyl injector was leaking. Thought it was the high pressure line but uon inspection it was the injector body. Had to take return apart and hold downs to get to injector. Tightened the injector body and reassemble. Started right up again and no leak. Runs perfect. Adjusted idle and she seems all set. Ran it about 20 minutes with all looking good. So I guess sometimes less is more. Glad I did not keep pursuing getting injectors out. May try some penetrant for a few weeks and then loosen the hold-d0wns to see if compression will pop injectors. But if she continues to run well may just leave well enough alone. Thanks for the help here. All were good ideas.