Lifter question |
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Lifter question |
kkid |
Feb 11 2015, 10:20 PM
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#1
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Member Group: Members Posts: 343 Joined: 18-December 07 From: Oakland, CA Member No.: 8,483 Region Association: Northern California |
Got a quick question,
Is our lifter supposed to be convex on the camshaft side? Mines are all flat. Thanks in advance, kkid (IMG:style_emoticons/default/smile.gif) |
colingreene |
Feb 12 2015, 02:00 AM
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#2
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Senior Member Group: Members Posts: 729 Joined: 17-October 13 From: Southern California Member No.: 16,526 Region Association: Southern California |
All the parts ive seen have been flat.
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ChrisFoley |
Feb 12 2015, 08:07 AM
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#3
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I am Tangerine Racing Group: Members Posts: 7,925 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
Oem lifters are slighty convex.
When two new lifters are held together they should rock, not sit flat. If used lifters are held together and they don't rock - they are worn out. |
Mark Henry |
Feb 12 2015, 08:37 AM
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#4
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Oem lifters are slighty convex. When two new lifters are held together they should rock, not sit flat. If used lifters are held together and they don't rock - they are worn out. (IMG:style_emoticons/default/agree.gif) flat or concave they are done. |
kkid |
Feb 12 2015, 11:34 AM
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#5
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Member Group: Members Posts: 343 Joined: 18-December 07 From: Oakland, CA Member No.: 8,483 Region Association: Northern California |
All the parts ive seen have been flat. Same here, they all must be 40+ yrs old. (IMG:style_emoticons/default/dry.gif) |
kkid |
Feb 12 2015, 11:45 AM
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#6
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Member Group: Members Posts: 343 Joined: 18-December 07 From: Oakland, CA Member No.: 8,483 Region Association: Northern California |
Oem lifters are slighty convex. When two new lifters are held together they should rock, not sit flat. If used lifters are held together and they don't rock - they are worn out. Thanks Chris for clarifying this. Haynes and above mentioned reason made me confused. How about the aftermarket lifters like this Scat lifters? http://www.pelicanparts.com/catalog/SuperC...L_pg2.htm#item5 Can I use these if the cam lobes are clean with no damage? |
Jake Raby |
Feb 12 2015, 11:54 AM
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#7
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Crown radius dictates lifter surface speed, which is directly related to point loading, and ultimately, wear.
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kkid |
Feb 12 2015, 11:56 AM
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#8
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Member Group: Members Posts: 343 Joined: 18-December 07 From: Oakland, CA Member No.: 8,483 Region Association: Northern California |
Oem lifters are slighty convex. When two new lifters are held together they should rock, not sit flat. If used lifters are held together and they don't rock - they are worn out. (IMG:style_emoticons/default/agree.gif) flat or concave they are done. If I find a concave lifter, does this mean the lobe is done too? It's very hard to see the condition in the cave even with a strong light. So I might wanna split the case to make sure. Thanks! |
ChrisFoley |
Feb 12 2015, 12:20 PM
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#9
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I am Tangerine Racing Group: Members Posts: 7,925 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
Generally speaking, the cam and lifters have to be properly matched at time of installation.
For instance, its not safe to install new lifters to go up against a used camshaft, or vice versa new cam/used lifters. |
Mark Henry |
Feb 12 2015, 12:26 PM
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#10
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I know I'm going to get shit for this one (IMG:style_emoticons/default/dry.gif) (IMG:style_emoticons/default/biggrin.gif)
Being a cheap Canadian I've reused stock cams many times without ill effects. Damage to the cam is often obvious, pitting, scoring and it can wear a divot into the cam. Measure the lobes they should be close to the same. I measure on V blocks/dial indicator for runout on the center bearing surface. Polish with 800 grit paper and I'd use new OE german lifters. But I haven't done this in at least 10+ years because to me it's no longer worth taking the chance. BTW I do have a mystery cam, aftermarket bolt on, no grind numbers and no history, looks close to stock with matching and order numbered good lifters. Came out of a engine that was supposed to be rebuilt, but some idiot power washed it and the cylinders were full of water. |
Steve Snyder |
Feb 12 2015, 05:41 PM
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#11
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Member Group: Members Posts: 241 Joined: 10-June 08 From: Graham, NC Member No.: 9,158 Region Association: South East States |
Generally speaking, the cam and lifters have to be properly matched at time of installation. For instance, its not safe to install new lifters to go up against a used camshaft, or vice versa new cam/used lifters. (IMG:style_emoticons/default/agree.gif) Not matching the cam and lifters is a risk not worth taking IMHO. |
kkid |
Feb 12 2015, 10:34 PM
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#12
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Member Group: Members Posts: 343 Joined: 18-December 07 From: Oakland, CA Member No.: 8,483 Region Association: Northern California |
Thanks guys for the inputs.
So I change either whole thing(cam and lifters) or nothing. As being cheap I might wanna change nothing this time then I don't have to split the case. But there is another reason why I might wanna open the case. I see slight oil leak from the mating surface on the bottom so I thought resealing is a cure. |
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