PDA

View Full Version : Duramax Fuel vaccum gauge wanted



Philsauto
06-18-2007, 22:28
I am looking for a tool to check the suction side of the fuel system. I understand this is a good way to test for restricted fuel filters and also to test for fuel pump suction. I'd like to not have to pay the $500 or so that Kent Moore wants for the "official" tool. Does anybody have anything like that available in an aftermarket style?

DmaxMaverick
06-18-2007, 22:31
www.kennedydiesel.com

A LOT less than $500.

Duramaster
06-19-2007, 08:14
Yeah............. I broke the shops gauge yesterday................. I left it laying under the hood on the inner fender of a Chev C-5500. It fell out on the road and was run over repeatedly. I can't wait to see how much this costs! :o It is/ was the Digital remote pressure/ vacuumgauge P/N CH-48027 (Kent-moore).

Philsauto
06-19-2007, 08:20
www.kennedydiesel.com

A LOT less than $500.

>>>
Thanks, Dmax. I went straight to John's site and ordered the tool.

Carrying on the injector subject from the other thread, I found a GM dealer who would provide me with the parts for the injector replacement. They didn't have the head gaskets in stock, and in fact had to get them from the DMAX plant, which seems strange to me. The left and right gaskets are of a different thickness, but we ordered them according to the position of the holes in the end of the old gasket.

Do you have any special warnings for reassembly?

More Power
06-19-2007, 12:49
Determining what head gasket thickness is required is based on piston protrusion. Last I heard there were 3 different ones available.

If this is an LB7, be sure to get someone experienced with injector cup seals to help out. :)

Jim

Duramaster
06-19-2007, 13:13
There are three grades (thickness) of gasket along with right and left. If you haven't messed with the pistons or the bearings, then just use the same grade of gasket that you took off. As far as stock goes, head gasket failure isn't really all that common so there aren't many dealers that stock them. Also, DO NOT reuse the head bolts. They are torque to yield bolts. Do not clean the lubricant off of the new head bolts. Do not apply anything to the head bolts but do clean the bolt holes out in the block with brake clean or solvent. :)

Philsauto
06-20-2007, 07:19
There are three grades (thickness) of gasket along with right and left. If you haven't messed with the pistons or the bearings, then just use the same grade of gasket that you took off. As far as stock goes, head gasket failure isn't really all that common so there aren't many dealers that stock them. Also, DO NOT reuse the head bolts. They are torque to yield bolts. Do not clean the lubricant off of the new head bolts. Do not apply anything to the head bolts but do clean the bolt holes out in the block with brake clean or solvent. :)

Ok, I appreciate the added info. Yes, I just ordered the same thickness gaskets that were on there. I ordered new head bolts and the dealer sent ALL the bolts, including the allen head bolts that go along the top. Do you see any reason to replace those?

Duramaster
06-20-2007, 08:09
Technically, no. That is if you are referring to the four upper 5 mm headed bolts at the top of the head (just seals cranckcase area). I replace them anyway. Any head gasket that I have done has always been warranty. Are the allen heads rounded? That would be another reason to replace them. :)

Kennedy
06-20-2007, 11:35
I must have missed something with the new KM gauge. I had the old one and destroyed it on a truck with a severe restriction. If memory serves it wa $170-ish. It was of very poor quality and readings varied based on position of the gauge (it had a hose) rendering it pretty useless in my opinion.

Philsauto
06-21-2007, 07:50
I must have missed something with the new KM gauge. I had the old one and destroyed it on a truck with a severe restriction. If memory serves it wa $170-ish. It was of very poor quality and readings varied based on position of the gauge (it had a hose) rendering it pretty useless in my opinion.

I don't work for a GM dealer but I understood they replace that one with a more expensive unit that was closer to $500. So I appreciate being able to buy yours for $150!

Philsauto
06-24-2007, 16:09
Determining what head gasket thickness is required is based on piston protrusion. Last I heard there were 3 different ones available.

If this is an LB7, be sure to get someone experienced with injector cup seals to help out. :)

Jim

Jim,
It is an LB7. But the injector sleeves were no big deal at all. None of them were leaking at all that I could tell, but I went ahead and replaced them all, along with their respective o-rings. I installed them with lock-tite sealer on the lower surfaces where they mate with the heads.

I used the same thickness head gaskets as what came off. My one disappointment was that the new design head gaskets are hard to come by. The left one, which is the one that was leaking, was the new design and came with instructions for the lower torque. The right one was the old design that was simply relabeled with the new part number. They told me there was no delivery date scheduled for the new design gasket. I used the torque specs from the old gasket for the right side, which is 150 degrees beyond the 59lbs, rather than 60 degrees twice for the new design. If they hold up another 150,000, I'll be happy.

The job worked out very satisfactorily as far as I can tell. The cooling system no longer pressurizes, and with the new injectors the smoking idle is gone and it is smoother than ever. It is too early to tell, but I'm quite certain the coolant consumption has stopped.

I took pictures all the way through the process which helped a great deal on reassembly. I kept track of my hours. It took me 10.5 hours to disassemble and 20 hours to clean up, replace injector sleeves and injectors, and reassemble. Next time I assign the job to one of my techs as this kind of work is hard on my body, and what's the point of owning a shop if you can't delegate work to other techs? But I'm glad I did this one myself. I feel much more competent to diagnose and repair now. I installed a BD exhaust manifold from Kennedy Diesel on the left bank while I was at it. The factory one really does look restrictive.

I did find a GM dealer that agreed to help me out by supplying the warranty parts and letting me install them. I don't get any labor, but since I had them out anyway, it certainly was the more sensible way to do it, and besides I feel better knowing I did the job carefully with no flat-rate short cuts. I have not gotten credit yet for the parts as I haven't returned them yet, having just finished the job yesterday. I'll report back if there is any trouble.