Stuck fuel injector.

[donncha]

I have posted this on the Yanmar group on yahoo, but didn't receive many replies.

I have a 3gm30 and the fuel injectors are in dire need of servicing, one of them is also leaking leading to loosing compression in one of the cylinders. I have successfully removed two of them without much effort, tapping abound with a hammer and a bit of timber.

The last one however is stuck fast, I have even gone as far as to take the injector apart, and all that's left is the lower section of the injector.

I know I need a new injector now but lets forget about that for now.

It was recommended to me by a diesel injection specialist to try and construct a slide hammer, a piece of 20mm studding fits perfectly into the bottom section of the injector but it still wont budge despite my best efforts.

I don't think the injectors have ever been serviced and it's quite an old engine (1984 I think). I have used copious amounts of diesel as well but to no
avail.

The space around the injector makes access very difficult to the injector, but I have removed practically all obstructions bar the cylinder head.

I did receive a suggestion to perhaps use the compression of the engine to pop it out. This seems daft and dangerous to me.

Any suggestions short of getting a new engine?

 

[earlybird]

If it's that stuck, I think your slide hammer idea is the best bet. Get a longer piece of studding. Get a heavier slide weight and really bang it upwards. I would envisage say 2 ft of studding and 4 or 5 lb. of weight at least. If that's no good, make it bigger still.

 

[oldharry]

"I did receive a suggestion to perhaps use the compression of the engine to pop it out. This seems daft and dangerous to me."

Not so daft: you just need to cover the injector with some old blankets to stop it going in to orbit through your cabin roof. If you are worried, put a piece of timber or ply over the blankets.

 

[Nigelhg]

Slide hammer works for most stuck injectors, but could you try making up some sort of puller. Some manufacturers even make their own special tool for remong injectors maybe yanmar themselves have a solution. I assume you've tried freeing it by giving it a small twist first and then trying a slide hammer. Hope this is some help.
Btw you can buy injector slide hammers on ebay for aroung £20...that's were I got mine

 

[savageseadog]

Instead of a slide hammer you could use a short piece of chain attached to a hammer or lump of metal. You can attach using welds, bolts or whatever necessary.

 

[mikejames]

I actually once slackened the injector clamp bolts on a 1GM and then forgot. Turned over the engine to try to check something else - it fired and the injector came out rather faster than I would have liked but the clamp held it.

 

[brianhumber]

It is amazing how strong carbon can be. Would agree with others try a bigger and heavier slide hammer first.

This used to happen at sea with the big 900mm bore 2 stroke marine diesels. We used to take the cylinder head off with the crane up end it and twat the injector end with sledgehammers.
The MOD furnace oil we got given by the Navy in the Falklands do was the worst for this and at one stage I was having to stop and do and do an injector change every 24hours- leaving them in just meant trouble getting the injectors out or then you had to get the head off and perhaps finding you were also lifting the liner out with it. You were deep in the poo then.

Morale of the story is do not run with smoky sooty exhaust even with small engines.

Brian

 

[smeaks]

try a good application of redex around the injector. Leave to soak and the if the stud iron does screw into the errent injector body can you construct a simple strong back by drilling a hole in some angle, support on blocks and jack the beast out?

 

[Slinky Spring]

I had the same problem with my 1GM10. In the end I had a puller made especially to get it out.
If you promise to send it back I could send it down to you.
PM me if you want to borrow it.
Dont worry about the injector because you have taken it apart. Mine went back together and works fine.

 

[donncha]

Thanks for all the suggestions.


As far as the compression popping goes, I think I'll leave that one til last, I'd prefer to give everything a good clean before turning the engine over, even by hand.

Might give that chain idea a go. It seems a little simpler then constructing a slide hammer out of that studding, I can't think of any other way to make the slide then casting a weight in lead.

I'll check out the slide hammers on the internet, but seeing as I'm in a bit of a hurry I may end up making my own.

SlinkySpring, I wouldn't make you go to all that effort of sending it to Ireland, but if you could describe the puller to me I would be very grateful, or a photo if you have one.


The injector if totaled by the way, I gave the threaded part that the fuel line goes to a whack in the intention of freeing it that made the thread unusable.

 

[Slinky Spring]

Central large bolt fits into the remaining portion of the injector after you have split it and the outside two fit loosely into the holes that studs have come out of.
It would be no problem to send it over. I am away now for the weekend but if you want it send me a PM with your details