t4 hydraulic cam, Trying to identify a hydraulic cam |
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t4 hydraulic cam, Trying to identify a hydraulic cam |
brandomc |
Mar 24 2010, 04:19 PM
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#1
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
I gave up on the 350 dollar 1.7 that i tried putting into my car, so now im tearing into a 2.0 i bought a while back. The guy i bought it from said that he had it rebuilt about 10 years ago and then was never able to get it to fire up. Anyways, he told me that it had hydraulic lifters in it, but he didnt know much else.
What i am wondering is how to tell the difference between a hydraulic cam and a solid lift cam. There are hydraulic lifters in the engine. Im tearing into this engine and trying to make sure everything is legit in it, but now that im almost completly disasimbled, im thinking about a 2056 kit for some reason. The engine looks pretty good inside. The rings look brand new, the cylinder walls look like they were honed a few hundred miles ago, the cam looks new, the pistons look old and one has a big ding in the top. A few of the cylinders have fins broken on the top. Looks like the engine was "freshend up" with not much money being spent. Im not sure if i should put it back together and try it out, or if i should just drop some cash and put together a really good engine. |
Mark Henry |
Mar 24 2010, 04:39 PM
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#2
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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 |
Pull the pump, aftermarket cams are most times marked around the pump drive.
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brandomc |
Mar 24 2010, 05:19 PM
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#3
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
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Mark Henry |
Mar 24 2010, 05:23 PM
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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 |
If marked yes you can tell. Most cam grinds have number codes.
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brandomc |
Mar 25 2010, 10:43 AM
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#5
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
If marked yes you can tell. Most cam grinds have number codes. I pulled the pump last night and the cam doesnt have any markings on it. I can look inside the engine and see the cam itself, so is there any way to tell by the shape of the lobes if it is hydraulic or not. The cam looks to be brand new, and they hydraulic lifters are new also. Im thinking that they were purchased together, but i dont like to trust what previous owners did. |
McMark |
Mar 25 2010, 10:50 AM
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#6
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Is the cam gear held onto the cam by bolts or rivits? (are they round or hex)
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brandomc |
Mar 25 2010, 11:54 AM
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#7
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
Im also trying to figure out if these heads need reworked. One of the heads has a bunch of dings . Here are some pics of the cam and heads.
So you can see how far i have disasembled the engine. There is a big ding on the top of one of the pistons, and a crap load of little dings on one of the cylinder heads. The cylinders look to have been honed not that long ago. The heads are really clean other than in the combustion chamber. The lifters and cam look new. The pistons have some scoring on the sides, but the rings look new. |
brandomc |
Mar 25 2010, 11:55 AM
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#8
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
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McMark |
Mar 25 2010, 12:56 PM
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#9
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
The five round dots looking through the oil pump bore tell me it's a stock gear of some sort. If it was a WebCam, Elgin, etc it would be bolted on.
What's the serial number on the case? If you want to have a long running motor, rebuild the heads with a reputable source. If you're building a 'quickie' then run 'em and cross your fingers. I always assume a used head will drop a valve seat at some point. |
brandomc |
Mar 25 2010, 01:08 PM
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#10
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
The five round dots looking through the oil pump bore tell me it's a stock gear of some sort. If it was a WebCam, Elgin, etc it would be bolted on. What's the serial number on the case? If you want to have a long running motor, rebuild the heads with a reputable source. If you're building a 'quickie' then run 'em and cross your fingers. I always assume a used head will drop a valve seat at some point. How can i tell if new valve seats have been installed. I plan on taking the heads apart and inspecting everything. Who does good work on T4 head in Los Angeles? |
McMark |
Mar 25 2010, 01:22 PM
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#11
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
No GA motor had a hydraulic cam stock. So if that IS a hydraulic cam, someone did something really odd with that motor. Len Hoffman (HAM, Inc) is pretty good at spotting things from a picture (if you post bigger versions). That's probably your best bet.
The chambers don't look like they've been flycut, which is bad and often skipped by non-reputable shops. Other common 'fixes' by non-reputable shops; grinding the valves and seats instead of replacing them, reusing worn out valve springs, reusing sodium filled exhaust valves, etc. Unfortunately, our heads are so touchy that you either spend some serious $ doing it right, or you slap it together and hope for the best. Mixing the two is a recipe for wasting $. |
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