fuel pump push rod questions
Thread Starter
Le Mans Master
Joined: Apr 2011
Posts: 6,284
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From: Hermosa
fuel pump push rod questions
I have a new re-built engine and the fuel pump decided to quit. Got it all apart and noticed that the bronze tipped fuel pump push rod has some signs of wear on it. The face that rides on the cam lobe is no longer perfectly flat.
Is the fuel pump push rod supposed to rotate in it's bore like a flat tappet cam lifter?
Should I expect to see some wear on this bronze tipped push rod? The engine has only been in service for a few hundred miles. I'm wondering how it will look after a few thousand.
The reason for the bronze tip is this is a Lunati retro roller cam set up.
I also checked to see if the fuel pump cam lobe had gone flat. The pushrod only moves in and out about 1/2 inch or so. Does that sound about right?
Is the fuel pump push rod supposed to rotate in it's bore like a flat tappet cam lifter?
Should I expect to see some wear on this bronze tipped push rod? The engine has only been in service for a few hundred miles. I'm wondering how it will look after a few thousand.
The reason for the bronze tip is this is a Lunati retro roller cam set up.
I also checked to see if the fuel pump cam lobe had gone flat. The pushrod only moves in and out about 1/2 inch or so. Does that sound about right?
Le Mans Master
Joined: Mar 2008
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From: Oxford MA-----You just lost the game!!!!
They make 'em with roller tips, check this out:
http://www.summitracing.com/parts/cc...make/chevrolet
Scott
http://www.summitracing.com/parts/cc...make/chevrolet
Scott
Team Owner
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
When I took apart my 434 SBC I had a heck of a time getting the what was left of a bronze tipped fuel pump rod out of the block. It was nearly warn away and kind of mushroomed so it would not come out of the block. Once I had the motor torn down on a stand I had to emery cloth sand away the mushroomed head to get it to come out.
Bronze tips are kind of a POS and I bought the roller for the new refresh.
Bronze tips are kind of a POS and I bought the roller for the new refresh.
Thread Starter
Le Mans Master
Joined: Apr 2011
Posts: 6,284
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From: Hermosa
Bronze tips are kind of a POS and I bought the roller for the new refresh.
I really don't want to have to shell out the cash for a roller tip push rod and I sure don't want the current one to mushroom to the point that it can't come out then I'm SOL for replacing it until the engine gets torn down. What to do......?
Thread Starter
Le Mans Master
Joined: Apr 2011
Posts: 6,284
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From: Hermosa
Are you sure you need a bronze tip? I have a Crower retro roller that uses the stock fuel pushrod.
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Thread Starter
Le Mans Master
Joined: Apr 2011
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From: Hermosa
Team Owner
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From: altered state
St. Jude Donor '05
Use the Howards composite pushrod love it. Never go back to another steel one running a billet core cam fwiw
Weighs a few ozs at best strong doesnt show any wear.
had arp (??) bronze tip was noisy kind of sloppy in the bore this one is nice and snug.
Weighs a few ozs at best strong doesnt show any wear.
had arp (??) bronze tip was noisy kind of sloppy in the bore this one is nice and snug.
Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
"Ultra Lite billet fuel pump pushrods weigh only 0.9 oz. (27 grams) to eliminate fuel pump cavitation. Gentle on the cam lobe,"
Seems to me the pressure on the cam lobe would come from the pressure of the spring inside the fuel pumps, saving a gram or two in the push-rod itself ain't gonna do squat.
I have the Comp Cams roller tip and it has lived in my car for 8 or so years with RPM's up to 7000. Been checked twice, the last time this summer and it looks and rolls like it was brand new. I would endorse this product
Seems to me the pressure on the cam lobe would come from the pressure of the spring inside the fuel pumps, saving a gram or two in the push-rod itself ain't gonna do squat.
I have the Comp Cams roller tip and it has lived in my car for 8 or so years with RPM's up to 7000. Been checked twice, the last time this summer and it looks and rolls like it was brand new. I would endorse this product
Thread Starter
Le Mans Master
Joined: Apr 2011
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From: Hermosa
Decided on the Howard's carbon polymer push rod from summit. Should be here by wed. If the fuel pump was easier to get to I'd put it together today with new pump so I could do some tuning. Guess I'll wait though given the PITA access to it.
Team Owner
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Thread Starter
Le Mans Master
Joined: Apr 2011
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From: Hermosa
Are these durable enough for street use?
Maybe cuisinartvette could tell us how many miles he has on his and if he's had any issues.
Last edited by REELAV8R; Aug 27, 2013 at 04:15 PM.
Had a 1976 L-82, 4-sp
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From: Some days your the dog and some days your the hydrant.
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Edit: I also use a Howard's composite distributor gear, fwiw.
Last edited by resdoggie; Aug 27, 2013 at 08:12 PM.
Team Owner
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I am skeptical when it said NASCAR. They only make things for a 600 mile motors.
Comp Cams sent me a non sleeved billet SR cam after a month of waiting. Then they said I needed the poly Dizzy gear which they air mailed the next day out.
The bummer was race weekend with 80 psi shifting from 4-5 at 140 mph on the main straight
The motor went silent. So I stabbed in the clutch and tried to hit the key ............... I coasted off a fire exit dead. The poly gears had lost some teeth....... No spark or oil pressure and my race day was done
Comp Cams sent me a non sleeved billet SR cam after a month of waiting. Then they said I needed the poly Dizzy gear which they air mailed the next day out.
The bummer was race weekend with 80 psi shifting from 4-5 at 140 mph on the main straight
The motor went silent. So I stabbed in the clutch and tried to hit the key ............... I coasted off a fire exit dead. The poly gears had lost some teeth....... No spark or oil pressure and my race day was done
Thread Starter
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
I can see why you might question it. You have a valid point the word "nascar" also concerns me a little since it sounds like hype to sell something new.
In your case with the gear the component was in shear vs a push rod which will be in compression. So not necessarily apples to apples.
Thanks for the report resdoggie more than a couple hundred, maybe a few thousand would be a better test of durability.
71scgc, how many miles you got on yours?
In your case with the gear the component was in shear vs a push rod which will be in compression. So not necessarily apples to apples.
Thanks for the report resdoggie more than a couple hundred, maybe a few thousand would be a better test of durability.
71scgc, how many miles you got on yours?