Distributor gear on small block Ford

Hi, I have a friend with a Tiger that I installed a Crane Hydralic roller cam , retro fit lifters and Comp Cams stamped steel roller tipped rockers in his 289.
There is not a lot of oil in the top end of this engine and at Willow Springs the steel distributor gear failed (overheated) and I think it should be pressure fed. I have never done this modification and would like some recommendations from the forum as to how best to accomplish this.
Thanks, Dave
 
there is an allen plug behind the distributor shaft, drill as small a hole as you can to spray oil onto the shaft. i believe mine came with a .040 hole, don't remember for sure.
 

Randy V

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Dave,

Make sure you are running the gear recommended by the camshaft manufacturer.. There are some roller cams that have an IRON gear which would require an IRON distributor gear.
Since the gear has failed, make very sure that the cam gear was not damaged and that you flush the crankcase very well. Best bet is to pull the pan, remove the oil pump and flush the pickup tube and pump very well. Make sure that the metal bits have not eaten up the gerotor assembly in the pump.
 
+1 on the material mismatch. Generally the newer roller cams would require a steel gear but if that cam is older (made for the 289 and uses iron for the gear you'll have to use an iron distributor gear.......and, Randy is right - you should disassemble the whole thing and clean all the passages thoroughly. I have seen engines destroyed by pieces that were left after such a failure.
 
Assuming the material match is correct. A couple of things that are not often discussed that can wipe out the gear relatively quickly is incorrect end float of the installed camshaft and the thrust clearance on the distributor shaft. If a replacement gear is installed the distributor the correct dimension must be obtained before drilling and installing the roll pin. Drill at 90 degrees to the original. If either is not within spec, you are headed for similar trouble.
 
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If the sump is off it may be prudent to take a look at the oil pump, high pressure/volume oil pumps load up the distributor gears, one with an iffy relief valve could easily destroy a cam gear.

Bob
 
there is an allen plug behind the distributor shaft, drill as small a hole as you can to spray oil onto the shaft. i believe mine came with a .040 hole, don't remember for sure.

I will add that .040 hole seems rather large, I'd half that if possible, maybe use a brass plug to make the drilling easier. Don't see why a brass plug wouldn't work but might want to check with an engine builder.
 
The gear did not actually break, but finally failed due to lack of lubrication. There is evidence of overheating in the rocker arms as well. The cam itself was getting plenty of oil, everything looks good there. No metal bits in the pump or pick up. It does have a high volume pump and 2 (two) oil filters but owner does not see that as a problem.This has Crane retro fit hydralic lifters and Trick Flow push rods. It seems that the lifters control the amount of oil going to the top of the motor but Crane says there is no resistance there. Another cam is on the way and we will put it all togeter and run the oil pump and see how much oil we are getting up top and I will get back to you.
Again, thanks for your comments and suggestions.
Dave
 
I would be checking to ensure that someone has not installed restrictors in the block to limit oil to the lifter galleries and/or cam bearings.
 

Terry Oxandale

Skinny Man
I ran into a very unusual problem on my 289 that is very similar to this, during the initial startup after a rebuild/upgrade. I realized oil was not getting to my rockers other than the rear-most rockers. I investigated the issue and found the solid roller lifters where blocking the oil from flowing past the lifters from the rear to front (oiling starts at the rear and flows forward though the lifters), and from getting to the pushrods (it got hot fast at the top of the heads). What I had to do, contrary to the lifter manufacturers advice (they saw no problem with their lifter), was very slightly notch the lifters so that oil would flow from the lifter's oil pass-around groove to the oil supply holes in the lifter bores. It was closed off for the larger part of a revolution (only getting oil pass-through at the top of the lobe, and cut off by the lifter body the remainder of the revolution of the cam). Oil was getting to the rear lifters, but it got more and more scarce going forward in the block to where the front lifters weren't getting it at all. Below is a photo of the notching I had to do to make everything oil up well on the top side and in front. I still don't know if this was a "roller retrofit" issue or not, but the lifter manufacture stood by their claim that the lifters should work fine, which they did, but they wouldn't have for long.

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I ran into a very unusual problem on my 289 that is very similar to this, during the initial startup after a rebuild/upgrade. I realized oil was not getting to my rockers other than the rear-most rockers. I investigated the issue and found the solid roller lifters where blocking the oil from flowing past the lifters from the rear to front (oiling starts at the rear and flows forward though the lifters), and from getting to the pushrods (it got hot fast at the top of the heads). What I had to do, contrary to the lifter manufacturers advice (they saw no problem with their lifter), was very slightly notch the lifters so that oil would flow from the lifter's oil pass-around groove to the oil supply holes in the lifter bores. It was closed off for the larger part of a revolution (only getting oil pass-through at the top of the lobe, and cut off by the lifter body the remainder of the revolution of the cam). Oil was getting to the rear lifters, but it got more and more scarce going forward in the block to where the front lifters weren't getting it at all. Below is a photo of the notching I had to do to make everything oil up well on the top side and in front. I still don't know if this was a "roller retrofit" issue or not, but the lifter manufacture stood by their claim that the lifters should work fine, which they did, but they wouldn't have for long.

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Is this this not rectified by the use of a small base circle cam on the early blocks?

Bob
 
Small base circle would have been probable cause for that mod above along with many roller lifters being modeled on SBC paremeters & not configured for SBF gallery positions.
With the ball pivot rockers in use on Davids example oil should not be restricted to top end and deflecters use to direct oil flow into the ball of rocker pivot.
 
The oil gallery position on both early and late 302`s is in the same location in relationship to the cam. The early model 302 solid lifter also has its oil gallery relief in the same location as the later stock roller lifters. The implications of the wrong lifter/cam combo could deny the top end of oil.



Bob
 
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