Has anyone else had a problem with an Edelbrock manifold being warped? I bought a new RPM Airgap in '03 during construction, started using it in July '05. Ever since then I've been fighting a problem with oil getting in the cylinders, mostly #3 & #5. The right bank has always been fine. It clogs the plugs and drinks the oil. I used over half a quart in a 200 mile run. Recently the plugs fouled to the point of losing one cylinder. I have tried new gaskets, twice, new valve seals in the one head once. This is all in a totally new rebuilt 350. Today I tore it down again, after a compression check, and checked the manifold with a straight edge. Looks like about a .005 dip in the center between the ports on the problem side. I'm going to see if I can get an adjustment from the supplier, that's a big maybe. Otherwise its empty the wallet for a new manifold. Anyone else chasing oil in the cylinder problems?
Not that problem, but I bought a new one for my Chevy truck with a 454. Within a little over a year it developed a crack in the intake, causing a vacuum leak so large that it shut down 1/2 the motor. Non returnable, and not feasibly repairable. Waste of 250+ dollars. Intake manifolds are now on my list of never buy new. Along with standard car and truck tires and carburetors.
Any decent machine shop that does automotive stuff could square it ... NO PROBLEM ... Edelbrock is funny ... I had a issues with a Carb and they said sent it back ... I did ... they went all thru and sent it back ... perfect and NO CHARGE ... I two of their Stainless muffers come undone at the seams ... Tough luck ... No help ...
Are you using RTV for the front and rear seals or gaskets?? If you are using gaskets you will have a tough time getting that manifold to lay down and seal against the heads......if you are using RTV...don't allow any setup time, squeeze the beads and drop the manifold on to the motor. The gaskets really should take up that .005" but, the straighter the better.
yeah, I would have a shop clean it up a little... that and new gaskets should help or solve the problem.
Thanks for all the replies. I have used the rubber end gaskets and the last two times I used just the RTV. Same results. I also used the expensive gaskets recommended by the Edelbrock data sheet. I think the gap, or cupping, is actually more than .005. One side is flat, one has the cupping. Hopefully I can get a new manifold.
Take it to a machine shop and get it milled out flush. A cheap fix...well, A LOT cheaper than a new manifold.
You also need to take into account any angle milling or refacing that has been done to your heads. A routine rebuild would include surfacing the head gasket and intake gasket surfaces. Do this a couple of time and you start to get excess clearances on the manifold. Then if the heads have ever been milled for compression, especially at a serious angle, the manifold will need to be remachined to match from the start.
Again, thanks to all who replied. The nearest engine machine shop that does manifolds is 50 miles from me in Modesto, CA. The price is $85. I will take it there the next time I need to make the trip. Meanwhile I bought a new manifold and got the RPU on the road again. I checked the flatness of the new one before I put it on. I will be selling the old manifold. An additional factor was that I didn't put the first manifold on, the engine builder did. I didn't have the instructions that came with it and didn't know I was supposed to put some Permatex, or Edelbrock's equivalent, between the heads and the gaskets. That probably would have helped, but the .005 to .007 warp was the major contributor to the oil getting in the cylinders. She is all sealed up per Edelbrock's instructions now and hopefully the problem is solved.
Sounds like Edelbrock just sent out a fucked up, poorly machined part. You shouldn't need to put any glue between a manifold and gasket. Sounds like the manufacturer knows that they don't seal right... Last Edelbrock part I bought (new) was in 1986 or '87; a carb linkage adaptrer which had a hole drilled in the wrong place, and instructions to slot it. Sounds like nothing's changed since then. As much as I like hot rods, when I worked on cars professionally, I tried not to touch 'em. I've found that most aftermarket parts just don't fit as well as O.E.M.; that the phrase "custom fit" is short for: "customize everything in sight if you want this P.O.S. to fit". Damn, I'm feeling old and grumpy. Best o' luck w/ dealing w/ E-brock; I think they should have to take the piece of crap back, and kiss your ass for the time and $$$ wasted. -bill
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