2QM injector R&R

[O32]

The shop that machined my cylinder head removed the injectors. But they don't have heat insulator washer that fits under the injectors. I presume this is something I need to get.

Takes for ever for us to get parts it seems. Just wondered if others have R&R'd their injectors and had also to find those insulators. Part 103854-11490.

[Wotname]

Yes, they are needed but perhaps the old ones could be reused.
As these are common to many of the small Yanmar engines (marine and industrial), my experience is that they are stocked at all Yanmar agents.

YMMV

[Wotname]

You could try small tractor shops, some of these use small Yanmar diesels.

[O32]

I hope you are right about there being stock. I have asked our local store to check. I have not gone over to check yet, but the machine shop said the old ones need replacing.

I did check the on-line tractors store (Hoye). They seem a great resource and are very helpful. But the US$40 in parts I wanted to order would have ended up as C$100 by the time I got them I am interested to see what our local store will want for them!

[Wotname]

FWIW, I have seen some John Deere mowers with Yanmar engines and some of the eternal parts looked the same as Yanmar 2GMxx engines but I don't have specific info about the injectors in this instance.

[model 10]

I've annealed a thousand aircraft copper spark plug gaskets. It's a waste to toss gaskets after every 50- 100 hrs. It's easy to do and it makes them as good as new for a number of times.

[Wotname]

Originally Posted by Ecos

I've annealed a thousand aircraft copper spark plug gaskets. It's a waste to toss gaskets every 50- 100 hrs. It's easy to do and it makes them as good as new for a few times anyway.

Unfortunately the insulator the OP requires is not copper. It is described as an heat insulator and looks like a thick carbon washer about 1mm thick. I don't know the exact composition of the material but it isn't a common metal but more like a ceramic (yet still sort of "soft"). It sits between the injector face and the top face of the top pre combustion chamber piece. There are two copper washers in the pre combustion chamber arrangement and this insulator disc.

@O32, the insulator costs AU$15 in Oz.

[model 10]

Why do you need to replace it? Does it need to be re-surfaced?

[Wotname]

Just to be clear, this heat insulator also provides the seal between the injector nozzle face and pre com chamber in a similar manner a cooper gasket does in other engines.

I have never tried to reuse one but would love to know exactly what it is made out of; maybe I should experiment (aka destroy) with an old one.

[O32]

On the tractor sites, they call it a 'Fiber Washer". I though I read something about it being a laminated metal/fibre washer. It is supposed to keep heat from the injector, so must have some type of insulating material that can take high heat. Ceramic fibre is possible.

The shop had some difficulty getting injectors out - sent head to an injector shop who had a method of pulling injectors. Because I have to wait for delivery of the heat seals, wondering how easy it will be to install injectors once head is back on. Do they just slide in or need some force from hold down bolts? Torque specified is only 14.5 ft.lbs

[Compass790]

Originally Posted by O32

On the tractor sites, they call it a 'Fiber Washer". I though I read something about it being a laminated metal/fibre washer. It is supposed to keep heat from the injector, so must have some type of insulating material that can take high heat. Ceramic fibre is possible.

The shop had some difficulty getting injectors out - sent head to an injector shop who had a method of pulling injectors. Because I have to wait for delivery of the heat seals, wondering how easy it will be to install injectors once head is back on. Do they just slide in or need some force from hold down bolts? Torque specified is only 14.5 ft.lbs

the injectors are easy to install IF the hole they go into & the injector body are clean. You can get a small wire brush on a drill &clean the holes & the injector body & then paint but dont put a thick coat of paint on as they are a snug fit. If they were hard to get out it's a safe bet u'll need to clean them. Try the fit before you paint them as if they still tight mite be better with a bit of grease.

[Wotname]

Originally Posted by O32

On the tractor sites, they call it a 'Fiber Washer". I though I read something about it being a laminated metal/fibre washer. It is supposed to keep heat from the injector, so must have some type of insulating material that can take high heat. Ceramic fibre is possible.

The shop had some difficulty getting injectors out - sent head to an injector shop who had a method of pulling injectors. Because I have to wait for delivery of the heat seals, wondering how easy it will be to install injectors once head is back on. Do they just slide in or need some force from hold down bolts? Torque specified is only 14.5 ft.lbs

Very very easy. Slide in first copper washer, slide in first pre com chamber (it's keyed so only goes in one way), slide in second copper washer, slide in second part of pre com chamber, slide in "insulator washer", drop in injector, place collar on top of injector (must go with the "pointy bits" down), fit and torque the two 8mm nuts.

Quicker than it takes to write / read this post .

Yes, they have the appearance of some sort of fibre and they certainly don't have any metal component.

[Wotname]

Beaten by the Compass

[O32]

Originally Posted by Wotname

Very very easy. Slide in first copper washer, slide in first pre com chamber (it's keyed so only goes in one way), slide in second copper washer, slide in second part of pre com chamber, slide in "insulator washer", drop in injector, place collar on top of injector (must go with the "pointy bits" down), fit and torque the two 8mm nuts.

Quicker than it takes to write / read this post .

Yes, they have the appearance of some sort of fibre and they certainly don't have any metal component.

I haven't seen what shop did yet, but suspect the pre-chambers may still be in place. Shop has apparently thoroughly cleaned up head, so if so, sounds like injectors should be an easy install once I get the insulators!

[O32]

Originally Posted by O32

I haven't seen what shop did yet, but suspect the pre-chambers may still be in place. Shop has apparently thoroughly cleaned up head, so if so, sounds like injectors should be an easy install once I get the insulators!

Well, the pre-chambers are still in place (and the shop painted the head including inside the injector sockets and the top of the pre-chambers

I have cleaned them out and tried to get any bits of paint etc back out.

Now I see how that "insulator" seals. It is sort of like a Mexican hat with most of the top cut off. The open top fits up into a groove in the injector body. I mention this, because one groove is fine and the insulator intact. But the groove on the other is full of crud and the insulator won't go in. Old insulator may have disintegrated in there when shop removed the injectors.

I think I might take the head and injectors to our local injector shop and have them give the injectors a once over and then install them with new insulators.

How the heck do you get those pre-chambers out anyway?