LB7: injector cups
- Thread starter wisconsinduramaxredneck
- Start date
its a fairly large procedure you have remove all the injectors which in your case are under the valve covers so you're probably looking at for first timer 8-10 hours since lots of shit needs to be moved
There are instructions in the GM Specs section. They're not that expensive, but there is a special locktite required.
Biggest thing I can suggest is make sure the bottom of the cup and the seat of the heads are really clean so the loctite can make a good bond. I sprayed a little brake clean down to rinse the oil residue off just to be sure, but that's me.
What makes you believe you have bad injector cups?
When you say special loctite, what do you mean? You use the red, or so I'm told. You will need to get a special tool to pull the cups, or borrow one. Getting one out without it is difficult if not down right impossible. Here is the link where I got ours.
http://www.toolsource.com/injector-...103792.html?osCsid=q1jq8i8bqpfiksg097umeqrr22
Very important to get the cups seated right, and leave them alone for 24 hours to let the loctite harded up. We just installed our second engine in the race truck and the engine builder had installed one of the injectors incorrectly, (#8) and it filled the cylinder with water. Thank god it didn't fire, or we would have hydro locked the engine and totally ruined a new race engine. I would suggest you leave out the glow plugs in all the cylinders that you replace the plugs and before you fire the engine pull the injector wires an turn the engine over to make sure you don't have a leak. You'll know it if you do.
When you say special loctite, what do you mean? You use the red, or so I'm told. You will need to get a special tool to pull the cups, or borrow one. Getting one out without it is difficult if not down right impossible. Here is the link where I got ours.
http://www.toolsource.com/injector-...103792.html?osCsid=q1jq8i8bqpfiksg097umeqrr22
Very important to get the cups seated right, and leave them alone for 24 hours to let the loctite harded up. We just installed our second engine in the race truck and the engine builder had installed one of the injectors incorrectly, (#8) and it filled the cylinder with water. Thank god it didn't fire, or we would have hydro locked the engine and totally ruined a new race engine. I would suggest you leave out the glow plugs in all the cylinders that you replace the plugs and before you fire the engine pull the injector wires an turn the engine over to make sure you don't have a leak. You'll know it if you do.
There is no special Loc-tite
The red loctite is what you are suppose to use
the gel works 3 x as good as the normal stuff ( if that makes it special)
Like subman Said though GM spec say leave it untill the loc-tite is cured before adding coolant (12HRS MIN ) we have done it with sucess in less than that but that was a rush case
By advice is make darn sure the sealing area in the heads is clean....Most probloms are because of this I use a barrel brush conected to a cordless drill and clean out the old loc-tite from the heads ( it needs to be spotless IMO )
It is a fair bit of work and takes me longer than 10hrs,But Paint is a better mechanic than I:baby:
How do you know its a cup and not the head gasket? If/when you look at the cup it isnt that hard to tell it's leaking,sometimes they are craked also
The red loctite is what you are suppose to usethe gel works 3 x as good as the normal stuff ( if that makes it special)
Like subman Said though GM spec say leave it untill the loc-tite is cured before adding coolant (12HRS MIN ) we have done it with sucess in less than that but that was a rush case
By advice is make darn sure the sealing area in the heads is clean....Most probloms are because of this
I use a barrel brush conected to a cordless drill and clean out the old loc-tite from the heads ( it needs to be spotless IMO )It is a fair bit of work and takes me longer than 10hrs,But Paint is a better mechanic than I:baby:
How do you know its a cup and not the head gasket? If/when you look at the cup it isnt that hard to tell it's leaking,sometimes they are craked also
Good point,Also a shop vac with a small end to suck out coolant is handy
If your truck is only jacked up in the front the coolant tends to settle in the cylinders closest to the fire wall (ofcourse) and this will effect the seal on the loc-tite
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I think we used green loc tite??? Think its for use on liners, as in cylinder liners. Maybe it was just red though. I'll have to check to make sure.
Regardless, use some good stuff and be extra sure it's spotless in the hole and on the tube itself.
C-ya
Regardless, use some good stuff and be extra sure it's spotless in the hole and on the tube itself.
C-ya
GM recomends RED the gel just sticks better while installing IMO
Spread it on the bottom tip of the cup before install,I wouldnt be shy as it just washes away what ever doesnt cure