Total mystery : sheared off cambelt but valves ok!?

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Grifter
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Grifter
Posts: 95
Joined: Wed Oct 29, 2014 7:49 pm
Car: S13 ca18det

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Grifter
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The aluminium had rubbed off quite bad with the cam & it kind of disintegrated into silver flakes, il be using the newer camshafts I've got with the other head though don't think it's a good idea to use the same ones.

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PapaSmurf2k3
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Yup. You'll want to use the new head and new cams.

Grifter
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Ok just got my new head sorted & hopefully get it installed asap
When I was doing ny timing belt I may have over tightened it!
How much slack should the belt have from the top between thr cams

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float_6969
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follow the FSM procedure for setting the tension on the timing belt.

Grifter
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I've installed the head with swapping over the inlet manifold to the original one torqued it down & got new cams.
When I started it up it just ran over faster than it shoudve
I set the timing with a new gates tbelt kit with new idler n tensioner bit the two cam marks weren't exactly on the timing marks they were both close but about 2/3 mm above the backplate marks
When.I counted thr cogs between the cams they were 39cogs including both dotted cogs& thr crank to cam cogs were 48 including thr dotted ones
It's not exactly firing now seems as it wanys to but can't
The shafts may need timing again making the belt to align properly but with this gates belt it makes the cams turn everytime I try & pit on the belt
But could my.timing be off by mm's as all the cogs seem to be in place
This is hopefully the only thing left now then il get a clip on with it in biz :chuckle:

Grifter
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Ok ive had the timing set with the exact amount of cogs in between fired it up started for about 10secs with the high pitched whine again then it went off didn't start back up again don't understand with this now as I've got a new gates.timing kit

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float_6969
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Have you made sure you're actually getting oil to the head? There is a check valve in the block and if that valve gets blocked from something, the head will oil starve and ruin the cams and head, much like what you had shown before.

Grifter
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Right thanks float il check that but where is that located
Just a note today I took off the cams.& the exhaust cam was stuck solid cause one of thr can holders had rubbed into thr shaft l, weird cause they were all exactly put back on although the mashed holder was a duplicate off another head which was already on this newer head I bought its a number 3 holder duplicate in place for holder number 4!
When I removed thr duplicate holder thr ex cam started to move freely again leading me to believe that's the culprit.
How can I get this sorted I mean could I put on holder 4 from older head or see a machine shop to see if they could sort it out

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float_6969
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You cannot swap cam caps from another head. The cam caps are line bored with the head they're mated to as an assembly. That why they have to go back in the exact same spot in the exact same orientation on the exact same head they came from. It sound like you've got another ruined head and cam now.

Grifter
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I think your right float unfortunately I didn't.check when.getting the head.but one of the.caps was a.dupe, I've got another.(hopefully) better head n cams due soon will d check that beforehand but I should have.it up soon
But say I left the.bad cap off the.camshaft with the other caps installed would the engine be ok to run cause the camshaft would still be held tight with the rest

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float_6969
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NO! The cam WILL break. And when it does you'll bend valves.

Grifter
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Well I took the risk of starting the car without 1 cap cause I just couldn't stand it. It's coping well I must say but have q.better head on its way thus week & hopefully il have the job done properly but it's magic to hear it roaring again
Won't give it too much though as it's been so long already another week won't matter

Grifter
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Grifter
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Ok I've got it running hut it's defo sounding very tapped, I've just put on a link which show a vid of my rs13 run theres also a noticible ex blow but that's cause I left the ex downpipe loose just to get it running.
The lifters are quite noisy but its also off the ground of about 15inches, could that also affect its oil pressure as what could rectify the VERY tappety sound

Grifter
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Sorry guys got a problem with the clip let ke try again

Grifter
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Ok I think the clips uploaded correct now as it's seen the cars runnin real tappety
http://www.youtube.com/watch?v=lMSAp8DM ... ata_player

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float_6969
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Sounds like you have a collapsed lifter, maybe more than one. Have you checked oil pressures?

Grifter
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I've not checked it yet but that is what il do next asap, I've heard of additives to put in with the engine oil do you think that'll help.

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float_6969
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I've tried them all and none fix the issue.

Grifter
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Ok float thanks, see when I checked the lifters before installing.em all were bouncing in & back I even placed them.in oil when they were out hmm, what other way could I check conditions of the lifters or best I just replace the stiff ones

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float_6969
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http://mizpahprecision.com/pricing.htm

Been using them for lifters for a long time. I just buy a whole new set now and replace all of them and send them back the cores. Waaayyy easier. I haven't had one bad lifter from them so far, and I've probably bought a half a dozen sets from them.

Grifter
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Aha ok float thanks il b on top of that & get back asape

Grifter
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Ok I've sorted the lifters but I've got this bad hesitagon when I accelerate all looks good but this horrible hesitation is still there

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float_6969
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Any codes from the ECU?

Grifter
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Naa no codes but I did replace the intake manifold gaske

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float_6969
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vid? Sounds like weak ignition

Grifter
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I'v sorted out the crank sensor but get a whiff of air suction from the intake side.
Im guessing it may have a loose nut somewhere but all else is real good now im gonna try &upload a video asap

Grifter
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Ahh maan! Sorted Out The top but now when I'm driving im getting this ratling from beneath the gearstick. I thought it was a wheel problem but its defo something to do with the gearbox cause when shifting 1/2/3 it gives this loose parts rattling defo from the gearbox someone said it be the release bearing but that'll sound when its on gear continues but thi rattle gets faster with engine speed


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