Yanmar 1GM10 Injector Removal

[smth448]

Following my post about a smokey 1GM10 in the Autumn we have finally dismantled the engine and found it had a hole in the head. New head and exhaust elbow have arrived from Marine Power. (Excellent service by the way!). Now I need to transfer all the bits from the old head to the new. According to the manual you remove the injector from the head by removing the retaining plate and then "remove injector". HOW???? Does it pull out or does it unscrew. Don't want to ruin it so have not yet resorted to brute force. Bear in mind the head is now off the engine.
Can any of you engine experts out there provide some wisdom?

 

[Cloven]

Why not ask Marine Power - they are normally very helpful.

 

[Slinky Spring]

I had this problem a while back. Mine was completely rusted into the head. The injector is just a push in fitting and not a tight fit normally. I eventually had a puller made to extract the injector. I thought that it would come out easily once the rust cracked but instead the puller had to pull it all the way out.
If you would like to borrow the puller and will cover the postage I will be happy to send it down to you.
I have previously posted photos of the it on here but am unable to find them anymore

 

[Georgio]

One way to remove the injector if the cyl-head is still attached is to loosen the bolts and then turn the engine over, the compression stroke will (should) pop the injector out of the head.

With the Cyl head removed I guess this doesn't help...

 

[Slinky Spring]

Heard this suggestion when I had the problem but had no effect when I tried it. Engineers i spoke to seemed sceptical that it would work in any circumstances.

 

[smth448]

Thanks for the offer. I don't think rust is a problem for me, I just couldn't work out if the thing was just a push fit or had to be unscrewed. I was baffled because the injector housing and the pre-combustion chamber both have flats on their surface that look like they should take a large spanner.
Thanks for the offer of the puller I will try without first but will PM you if I need it.

 

[Slinky Spring]

No problem.
You may find it easier to work on the injector if you remove the two studs. Use the two nuts off the studs wound together onto each thread. With them tightened to each other you can just unscrew them from the head.

 

[Slinky Spring]

Just remembered that the injector has a projection in the casting that engages in a slot in the sleeve. You should therefore avoid turning the whole unit if you can help it as you may break off the projection.

 

[steve28]

Glad the advice was correct, have seen so many fail in this way. are you replacing the elbow as well ?
steve

 

[smth448]

Oh yes, new elbow bought at the same time!!
It was strange, the old one looked perfect, even when removed and inspected. It was only seen to be knackered when I filled the outer jacket up with water with finger over the inlet hole. Or rather I didn't fill it up as it all poured straight through. From the outside the elbow looked perfect, no different to the new one. Perhaps it should be a ten year replacement item. Much less expensive than a new head. Mind you mine could have been leaking for years. No way of knowing. The exhaust port on the head was covered in rust.

 

[cgb1998]

I am in the process of trying to replace the injectors on a 3HM35F which funny enough is part of the GM series. The injector is the same as the 1/2/3GM injectors.

I have managed to get 2 of the injectors out and will soon have the third out. I am not sure though what to do about the pre-combustion chamber. I need to replace the gaskets as injector blow by was the problem in the first place, but am not sure how. Can I get it out without taking the head off. The service manual is not clear about this at all.

Any help is appreciated.
Cheers
Colin