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Discussion Starter #1 (Edited)
I assembled the engine 2 years ago, and finally got it running, and drove it this past year. I trailered it up to Tn and drove it around the PITS show for 4 days, trailered it back home, and drove it a little down here.

After replacing my over ported head, but before starting it, I noticed that the distributor center shaft moved too much. I pulled the distributor and noticed that the teeth on the gear are worn, the edges of the teeth are worn sharp.

I replace the gear, oil, filter, and within 30 minutes of the engine running, driving the car, it has destroyed the gear on the distributor. One section of teeth are so worn down that the distributor is no longer turning.

I replace the oil pump, pickup, replace the gear, oil, filter, and within 1 min, I see it marring the new gear, complete contact on one side of the tooth edge.

I replace the distributor with a fairly well used Mallory, and after about 15 min of trying to get the engine to run (it's a dual point and not adjusted well) I stop and pull the distributor and see that it is starting to scratch the same edge of the distributor gear.

This is a Comp Cam Hydraulic lifter cam. Comp Cam recommends either they steel or composite gear. This is the steel gear that I have been replacing with. The oil is 10w-30. Before installing the distributor I lube the gear, and when I pull it out most of the lube is washed off and the gear has engine oil on it.

The first oil pump was a Melling standard, the 2nd is a TRW HV. The pump shaft has play, it is not binding.

The only other thing I can think of is somehow the gear on the cam has gone bad and is eating into the distributor gears. Any though on what I might be missing?
 

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Discussion Starter #3
From left to right 1st gear is the original, but over the past 6 months has worn the teeth sharp. 2nd is the one that lasted all of 30 minutes before wiping an entire section of teeth off. 3rd is the one where the engine ran for only about a minute. 4th and right most is the Mallory where the engine fired but did not run.


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did you assemble the engine? maybe the cam thrust plate has come loose and the cam is walking? that's a lot of metal going through the engine now, hope the bearings are ok.
 

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Discussion Starter #5
did you assemble the engine? maybe the cam thrust plate has come loose and the cam is walking? that's a lot of metal going through the engine now, hope the bearings are ok.
I assembled the engine and yes, put the thrust plate on. Is it loose and the cam is walking? When I had the intake off I pulled and inspected the lifters and they are all perfect. Unfortunately, now there is no way to see the plate until I take the timing cover off.

Metal in the engine, that is one reason I replaced the pump and pickup. Any of the debris should be stuck in the old oil filter.
 

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Discussion Starter #6
Its had 2 oil and filter changes in the past 3 days with less than 1 hour run time on the engine. It's not this often you can pull your dipstick to check the level and see that 100% clean oil still on the end of the stick. >:)
 

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When I put my GT40P in I spent some time trying to understand what I needed to do. So, here’s what I learned and believe is pretty accurate. First off is understanding what the cam is made out of. Ford factory cams are billet 5150 steel. They are fully machined even between the lobes. Ford used a steel distributor gear. Most aftermarket hydraulic roller cams are not billet 5150 steel. They are “SADI” or Selectively Austempered Ductile Iron. They are cast ductile iron that only the lobes are hardened. These cams you can use a regular cast iron distributor gear, the same as a flat tappet cam. I got this info from Howard’s Cams. Howard also told me all cam companies are buying their blank cores from the same suppliers.

This causes problems with distributor companies. I read a article by MSD said they as most aftermarket distributor companies use a Melonized gear. This is a hardened ductile iron gear. It’s the default material as it will work on flat tappet, SADI or billet Ford 5150 cams. I’m using a $29 MSD Melonized gear I bought at Autozone. I called MSD and verified it would work on a 5150 cam.

The other part of the equation is the gear must be properly located on the shaft. These MSD Melonized gears have only 1 roll pin hole drilled. You must drill a new hole through the distributor shaft 90* from the factory hole after you properly measured and located the new gear. MSD has a pdf on their web site how to do this.
 

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Discussion Starter #9
Is this a roller cam? If so, you are good with the steel gear. If you have a flat-tappet cam you are going to need to use a cast iron gear.
One is a correctly matched $80 Comp.Cams gear.

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Discussion Starter #10 (Edited)
Is this a roller cam? If so, you are good with the steel gear. If you have a flat-tappet cam you are going to need to use a cast iron gear.
Flat Tappet. Cast, steel, I purchased one of the replacements as the proper one from Comp Cams for $80. Ate it right up.

Just checked my purchases, they are all Cast Iron gears. My mistake earlier stating steel. .530 shaft.
 

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That looks the wear when you put an ordinary iron gear on a steel roller cam. I’d call comp and get with them. I’d try the melonized gear.
 

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Discussion Starter #12
That looks the wear when you put an ordinary iron gear on a steel roller cam. I’d call comp and get with them. I’d try the melonized gear.
Hydraulic flat tappet cam, not roller.

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I know, just saying that’s what it looks like. That second gear, where did it come from? Maybe there’s a bad batch, or some Chinese knockoffs running around. I’d still give comp a call, then maybe MSD and see what they recommend for a gear. How does the cam look if, you can shine a light down there and see that hopefully the damage is limited to the distributor gear.
 

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Time to buy that expensive magnet thing summit sells to snap on the oil filter....maybe not so expensive in the scheme of things! That sux...You buy good parts, put things together carefully,....and crap like this happens..I hope you get it figured out and no permanent damage to the motor.
 

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I assume you’re measuring the shaft for the appropriate gear placement?

I had an issue with a cam eating gears so we painted the teeth on the gear, and did a wear pattern test, just like on a third member, until we got the wear pattern where it needed to be. Then we pinned the gear in place.
 

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Couple of things occur to me,


1) The first gear damaged the cam gear and now the cam gear is damaging all the rest of the gears
2) The dizzy is either dragging dramatically or somebody modified it in such a way that the gear doesn/t mate correctly, shaft size is too small for the bearing surfaces, bearing surfaces including in the block could be toast... In any case, trying a different dizzy would be on my list.



Next time the pan is off, pull a rod cap just to see...


Good luck, these are teh worst kinds of problems where a new engine gets debris...
 

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Discussion Starter #18
Couple of things occur to me,


1) The first gear damaged the cam gear and now the cam gear is damaging all the rest of the gears
2) The dizzy is either dragging dramatically or somebody modified it in such a way that the gear doesn/t mate correctly, shaft size is too small for the bearing surfaces, bearing surfaces including in the block could be toast... In any case, trying a different dizzy would be on my list.



Next time the pan is off, pull a rod cap just to see...


Good luck, these are teh worst kinds of problems where a new engine gets debris...
#1 Is possible. #2, I changed distributors and it still happened .

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Discussion Starter #19
I assume you’re measuring the shaft for the appropriate gear placement?

I had an issue with a cam eating gears so we painted the teeth on the gear, and did a wear pattern test, just like on a third member, until we got the wear pattern where it needed to be. Then we pinned the gear in place.
Does it with 2 different distributors.

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Discussion Starter #20
I know, just saying that’s what it looks like. That second gear, where did it come from? Maybe there’s a bad batch, or some Chinese knockoffs running around. I’d still give comp a call, then maybe MSD and see what they recommend for a gear. How does the cam look if, you can shine a light down there and see that hopefully the damage is limited to the distributor gear.
Van gear is deep and off to the side, hard to see. I'm going to pull the timing cover this week and look at the cam. I'm thinking a replacement is in my future.

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