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Discussion Starter #1
A little frustrated with the Mustang’s performance last week. Very puzzled and hope I don’t have multiple issues. The oil pump was jammed up for sure and the distributor sheared the timing gear. I tracked all that down to a cheap roller rocker that came apart (engine builder said it would be fine). Parts do fail though, even expensive ones. However inspection during tear down, I noticed inconsistencies in how the rollers moved, not a good sign after just 10 hrs. use. Beyond that there seemed to be electrical issues before the motor quit that I hope are related to the pump seizing, but I don’t see how. The tach stopped working on several occasions and when the tach stopped, the oil pressure was good, but the motor was backfiring on deceleration and would not rev beyond what I estimate to be 5000 rpm. When the tach was working, 7K plus was no problem. MSD box tested good and distributor (MSD) tested good @ 570 ohms. During the weekend, pulling the rev limiter chip and re routing the coil wire seemed to help for a while. However after a spin out the issue seemed to return on and off until the motor finally quit on the last lap of the last session.

Other than that, all in all it was a great weekend. Pump jammed because one of the roller bearings got sucked up in the pump. Mains checked out good, probably thanks to the accusump doing it's job.

Any help would be appreciated.
 

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Discussion Starter #3
"Splurged" and bought a stud kit for the oil pan. The oil pan is a road racing version from Kevco and has always been a challenge to bolt on. There always seemed to be 3 or 4 holes that just didn't quite line up. The stud kit made install so much easier and for $13 was a good upgrade.

Didn't get as far as I wanted. Checked the rocker geometry and found the push rods too short for the new rockers, so Summit to the rescue.
 

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Discussion Starter #6 (Edited)
Frustrating rear main seal.. I don't know if any one else has had issues with aftermarket crank shafts and main seals , but I have. Never any issue with stock cranks. This one has been tough to seal and developed a leak shortly after the last rebuild. I was not surprised, the machinist used a felpro rubber gasket. I have had luck with the 2902 felpro and had one set aside, however this time, not so. I used a 1 piece oil pan gasket this time too. So to make 2 days of wrenching short, I went with a traditional oil pan gasket kit, 4 piece and a Cometic rear main seal. Success so far 30 minutes run time and no drips
 

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I have a junk yard GT40P in my 66 with a set of used genuine Ford Cobra 1.72 rockers made by Crane. I have to say they were very noisy. I was becoming concerned after 2nd66 and a couple other’s having oil pumps eat needle bearings I pulled them. I put the stock pedestal rockers back in. It’s a lot quieter along with piece of mine I eliminated a potential source of problems.
 

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I have a junk yard GT40P in my 66 with a set of used genuine Ford Cobra 1.72 rockers made by Crane. I have to say they were very noisy. I was becoming concerned after 2nd66 and a couple other’s having oil pumps eat needle bearings I pulled them. I put the stock pedestal rockers back in. It’s a lot quieter along with piece of mine I eliminated a potential source of problems.
My oil pump ate a piece of 50 year old cam bearing. the OE oil pick screen has a hole the size of a quarter covered by a strip of sheet metal genius design makes the screen worth less :| Needle /roller bearings in a engine make my nervous yeah you may get a couple ponies here or there but at the price of longevity ,great for a race engine that would get torn down a lot but ,,,,,
 

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Discussion Starter #9
Good news and bad from the track CMP, Carolina Motorsport park, . Good news, main seal is fixed! no more leaking. Bad news, loud pop coming out of 8 in 4th and no more 3rd and 4th, suspect issue with the main shaft. Engine felt a little weak. Left the ignition on in the truck and ran the battery down enough where it would not start, and we were almost the last ones there on Sunday, so I went to get the battery out of the Mustang and found the negative terminal loose! I will add the battery to the nut and bolt check list from now on. Will be pulling a transmission and waiting on brake brackets this week.
 

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Your time at CMP sounds about like the “fun” I had when I was there last. Glad you have the motor back together, sorry about the trans, but I have to ask, how does a roller bearing get past the oil pump screen? Just seems to me the screen should have kept it out unless it has a hole. ??

And odd to have the dizzy timing gear get trashed along with the oil pump getting seized. I’m not sure which is the chicken and which is the egg, but it sounds to me like, first the gear started to get destroyed, the timing changed, motor wouldn’t rev as it should because of that, and then perhaps something (roller bearing or gear bits) somehow found their way into the pump and was large enough to end the day.

Are you positive you have the right dizzy gear for the cam you are running?

Good luck with the tranny,
 

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A little frustrated with the Mustang’s performance last week. Very puzzled and hope I don’t have multiple issues. The oil pump was jammed up for sure and the distributor sheared the timing gear. I tracked all that down to a cheap roller rocker that came apart (engine builder said it would be fine). Parts do fail though, even expensive ones. However inspection during tear down, I noticed inconsistencies in how the rollers moved, not a good sign after just 10 hrs. use. Beyond that there seemed to be electrical issues before the motor quit that I hope are related to the pump seizing, but I don’t see how. The tach stopped working on several occasions and when the tach stopped, the oil pressure was good, but the motor was backfiring on deceleration and would not rev beyond what I estimate to be 5000 rpm. When the tach was working, 7K plus was no problem. MSD box tested good and distributor (MSD) tested good @ 570 ohms. During the weekend, pulling the rev limiter chip and re routing the coil wire seemed to help for a while. However after a spin out the issue seemed to return on and off until the motor finally quit on the last lap of the last session.

Other than that, all in all it was a great weekend. Pump jammed because one of the roller bearings got sucked up in the pump. Mains checked out good, probably thanks to the accusump doing it's job.

Any help would be appreciated.
What brand were these cheap roller rockers?
The only bullet-proof ones were stainless. Found out what happens to the lesser stuff when I was at JBA back in the 80's.
 

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Discussion Starter #12
Yep 2 separate issues, now 3. The rockers were no name stuff. Think back on it, I think they left the retaining snap rings off when they were made, cause while I did find 32 roller bearings in the pan, I found no retainers or anything like one. As far as the oil pick up screen, it is an after market one to match the pan I have and the screen on it has round holes, just large enough for a roller bearing to be sucked up in it when just right.
Pulled the toploader out and yep, the output shaft broke between the 1/2 and 3/4 gears. No real damage other than the shaft so it should be an easy fix. I always thought transmissions only broke when shifting or attempting to shift, both times, with mine it was in gear and rolling in and out of the gas.. once in 3rd and the last time was in 4th.. strange. Can't help but think the output shaft got damaged when the cluster gear failed last year causing the last failure.
 
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