Just adjusted valves, car won’t rev past 5k rp, What did I do wrong? |
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Just adjusted valves, car won’t rev past 5k rp, What did I do wrong? |
newto914s |
Jul 20 2005, 09:17 PM
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#1
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Senior Member Group: Members Posts: 561 Joined: 16-February 04 From: Thornton, CO Member No.: 1,663 |
This is the 4th time I’ve adjusted them and every time I do it I feel that I do a better job, but my car keeps sounding worse.
I adjusted them in April and the car sounded and performed great. Around 6 weeks ago I checked the compression and got some low reading (especially on #2, 60psi). So I thought I’d reset the valves and check the compression again. So I reset the valve clearance again and from that point my car has been driving funny. It was very clickity-clack, and wouldn’t rev past 5k. Now today I reset them again(3rd X in two months), less clicking, but still won’t rev past 5k, unless I only press the throttle down ¼ the whole time. Is this simple because I set them wrong, or could this be related to my low compression numbers, i.e. valve guides that are so far worn the extra .2mm is allowing valve float? 76 2.0 d-jet Thanks guys Samson |
Rand |
Jul 21 2005, 01:03 AM
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#2
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
Dumb question, just to be sure: What are the exact clearances you are setting them too (intake and exhaust), and what year/size engine?
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newto914s |
Jul 21 2005, 01:22 AM
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#3
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Senior Member Group: Members Posts: 561 Joined: 16-February 04 From: Thornton, CO Member No.: 1,663 |
.006(.15mm) intake .008(.2mm)exhaust I've read the bird board and a bunch of threads up here about setting the clearance and feel I have it pritty close, but who knows. |
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CptTripps |
Jul 21 2005, 06:22 AM
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#4
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:: Punch and Pie :: Group: Members Posts: 3,584 Joined: 26-December 04 From: Mentor, OH Member No.: 3,342 Region Association: Upper MidWest |
He has a 76 2.0 D-Jet. I heard the car after he'd done them. Sounded like a Diesel John-Deer tractor.
I'm going to be interested to see how this plays out. As I've never done a valve adjustment before, I need to see what to look out for. |
SGB |
Jul 21 2005, 06:38 AM
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#5
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just visiting Group: Members Posts: 4,086 Joined: 8-March 03 From: Huntsville, AL Member No.: 404 Region Association: South East States |
At the bottom of the Pelican Parts tech article on valve adjusting, there is an addendum of sorts where someone adds their version of the valve asdjusting proceedure- which valves are to be adjusted based on which valves are open- really helped my confidence in feeling like I was on the right mark (I always cross-checked to see if the timing marks showed on the impeller after I rotated the engine to get the different sets of valves to the "adjust now" position). Dang thats a long sentance. Hope it makes sense. Look at the "Valve adjustments made easy" tech article:PP valve adjust guide
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ArtechnikA |
Jul 21 2005, 07:06 AM
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#6
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rich herzog Group: Members Posts: 7,390 Joined: 4-April 03 From: Salted Roads, PA Member No.: 513 Region Association: None |
it may be that you did nothing wrong but there is a more serious problem.
when you adjust the valves, are they very far out of adjustment? valves that tighten up by themselves may be stretching. valves that loosen up by themselves may be dropping seats. both these conditions never get better by themselves and will eventually destroy the engine. could be you have a broken valve spring. it may be time to pull off the rockers and REALLY LOOK at the valves and springs. the valve adjustment procedure is not difficult once you "get it" but until it clicks in your head it can get confusing, so double-checking everything is always a good idea. i don't really know how else you'd check for serious valvetrain issues; hopefully someone with more experience with /4 engines will have better ideas/ |
redshift |
Jul 21 2005, 07:58 AM
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#7
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Bless the Hell out of you! Group: Members Posts: 10,926 Joined: 29-June 03 Member No.: 869 |
I think the valves are toast... exhaust valves.
M |
Cap'n Krusty |
Jul 21 2005, 08:58 AM
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#8
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
THE VERY FIRST THING you do is make sure you have solid lifters. Look at the valve gear and report back. Hydraulic setups most often have solid spacers between the rockers, solids have springs in there. If you determine they're hydraulic lifters, you set them differently. If they're solids, you use the method I've listed here in the last couple of months. Then you pull the motor and fix the compression problem. A valve adjustment ain't gonna be the answer. You have a hard time passing 5K RPM because you're dragging along a dead hole. You may also have a timing problem. The Cap'n
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Joe Ricard |
Jul 21 2005, 09:13 AM
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#9
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
I wish I could afford to travel around and fix these problems for people. You know You break it I'll come fix it.
Just think of all the cars that would be on the road now instead of on th jackstands. Sort of a mission of mercy. You know will fix it for food and beer and a place to rest my head. |
Allan |
Jul 21 2005, 09:30 AM
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#10
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Teenerless Weenie Group: Members Posts: 8,373 Joined: 5-July 04 From: Western Mesopotamia Member No.: 2,304 Region Association: Southern California |
Come rebuild my tranny and I'll supply ya with all the beer, food and rest you can stand. (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif) |
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tat2dphreak |
Jul 21 2005, 09:34 AM
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#11
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stoya, stoya, stoya Group: Benefactors Posts: 8,797 Joined: 6-June 03 From: Wylie, TX Member No.: 792 Region Association: Southwest Region |
get my car on the road, you'll have steak dinners, kegs of your favorite ale, a place to stay and I'll give you some cash too... where do I send the plane ticket? |
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Joe Ricard |
Jul 21 2005, 09:40 AM
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#12
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
(IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif)
Hmm guess I better get mine done tonight Huh? what kinda beer? Man that would be the coolest job. Drive around dispatched from the club. Somehow keep track of where I'm at and the closest broken car gets next dibs. or really BIG problems get priority somehow. Just think how long I would be in Kentucky (IMG:http://www.914world.com/bbs2/html/emoticons/blink.gif) Sorry RAND. (IMG:http://www.914world.com/bbs2/html/emoticons/hijacked.gif) |
tat2dphreak |
Jul 21 2005, 09:46 AM
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#13
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stoya, stoya, stoya Group: Benefactors Posts: 8,797 Joined: 6-June 03 From: Wylie, TX Member No.: 792 Region Association: Southwest Region |
you name the beer! I'll put a kegrator in the garage (IMG:http://www.914world.com/bbs2/html/emoticons/beer.gif) *only partialy kidding, if someone wants to come by and help out... there's not enough hours in the day for me right now. (IMG:http://www.914world.com/bbs2/html/emoticons/hijacked.gif) |
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newto914s |
Jul 21 2005, 09:46 AM
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#14
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Senior Member Group: Members Posts: 561 Joined: 16-February 04 From: Thornton, CO Member No.: 1,663 |
The valves were pritty close this time. A little loose, thus the John Deer sound track. During the ajustment that seemed to present all these problems, a month ago, #2 and #3 or #4 were tight with no clearance. I feel I "get it" with the valves. I did it in 2 1/2 hours this last time, compared to 8 my first attempt. |
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bd1308 |
Jul 21 2005, 09:47 AM
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#15
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
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newto914s |
Jul 21 2005, 09:54 AM
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#16
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Senior Member Group: Members Posts: 561 Joined: 16-February 04 From: Thornton, CO Member No.: 1,663 |
I'll check the lifters, can I see the valve gear without pulling the engine. Timing is fine. The deal with a valve adjustment not curing my problem, is that it pulled fine to the redline prior to the valve adjustment. Now it doesn't. I should have left #2 stuck and I think all would be fine (IMG:http://www.914world.com/bbs2/html/emoticons/screwy.gif) |
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Dave_Darling |
Jul 21 2005, 12:57 PM
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#17
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914 Idiot Group: Members Posts: 14,986 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Sadly, that's not enough of an identifier any more. The solid spacers have been sold as "upgrades" for Type IV/914 engines for years, so even if you find them it's not necessarily an indicator of hydro valves. I don't know if the "hydro kits" include the spacers necessarily, so finding springs is not a definite indication of solid lifters either. (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) The only ways to tell that I know of are to pull the pushrods and/or the lifters. The pushrods should be shorter and I think thinner if you have hydro lifters, but I don't know the exact lengths or widths. The lifters will be a bit longer and will look different than the solid ones, I believe. --DD |
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newto914s |
Jul 25 2005, 08:31 PM
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#18
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Senior Member Group: Members Posts: 561 Joined: 16-February 04 From: Thornton, CO Member No.: 1,663 |
I think you're right! (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) So this would be why anything over 5k rmps is unattainable. Is it possable to fix this valve with out pulling off the head? With the pain-in-the-@ss factor, and the "just do it right" advice aside, is it possable? I'm thinking quick fix so I can feel somewhat safe driving out to MWC. |
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newto914s |
Jul 25 2005, 08:31 PM
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#19
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Senior Member Group: Members Posts: 561 Joined: 16-February 04 From: Thornton, CO Member No.: 1,663 |
Opps!
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redshift |
Jul 25 2005, 08:33 PM
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#20
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Bless the Hell out of you! Group: Members Posts: 10,926 Joined: 29-June 03 Member No.: 869 |
Ouch..
No. Headwork is expensive, but not REEEEEEAL expensive... hmm... valves... how much for parts and labor, Rimco, and SS valves fellas? RON!!!!!!!!!!! Holy sheepdip... sorry to be right this time. (IMG:http://www.914world.com/bbs2/html/emoticons/sheeplove.gif) M |
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