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steeny · Posted: Sat Jul 22, 2006 1:58 pm Post subject: cam lobes worn down

i need a new cam, dont i?

seems intake lobe on 1 and exhaust on 2 are both stuffed, theres even material deposited on the followers.

Intake on 1

Follower on 1

intake and exhaust on 3

the question now is do i throw more good money after bad? A new cam is AUD$ 530. followers are AUD$92 each. thats assuming everything else is OK.

this is really annoying since i was so close to having it back on the road. all i had to do was adjust the valves (so i thought), reinstall the passenger seat, and spend a few hours working through electrical gremlins. now , in the ten minutes its taken me to remove the cam cover, i'm up for a top end rebuild at the very least, and another grand or so of parts.......
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1978 924 N/A
she's gone.....

Ozzie · Posted: Sat Jul 22, 2006 2:16 pm Post subject:

I'd be lookin at a good second hand one if I were you.
Contact this guy- He's helped me a lot.
admin@porsche-9xx-parts.co.uk
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

flosho · Posted: Sat Jul 22, 2006 2:57 pm Post subject:

I would look for a good conditioned used cam. You could buy an aftermarket piper cam or cam from integeral and have it shipped for the price of a new one...
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[This Space For Rent]

steeny · Posted: Sat Jul 22, 2006 3:00 pm Post subject:

yeah. i haven't contacted aporschapart yet either. they are normally pretty good if theres a secondhand one available.

thing is the engines only done about 3000 since the last service (mind you its taken me nearly 3 years to do those K's and the cars been off the road for about a year now). i'll have to dig out the receipt for the service and see if teh valves were adusted. surely that sort of damage doesn't occur in under 5000K?
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1978 924 N/A
she's gone.....

leadfoot · Posted: Sat Jul 22, 2006 4:12 pm Post subject:

You can get a complete head for $1000 from one of the euro parts places in richmond, I think it might have been ASV european but they were always listed in the trading post under european auto spares... they might have a better price on a single cam...

Now depending on the amount of wear there are options for you, is the head off ??

Take measurments of the current lift and phone Crow cams and ask if they can regrind on a smaller base circle to be able to take up the slack with shims... they might be able to resurface the lifters for you and add material otherwise I can think of another shop where they probably can do this...
They quoted me a grind a while ago for about $120...

The other option is to get a grind from Wade cams... I had my valves lengthened though as opposed to using shims, the lift is reduced but the duration is increased on the grind I went for...

My head was rebuilt at Gowan Hindhaugh in Box hill for around $330 add an extra $150 for a new gasket kit from aporschaparts... I have new valve guides that I didn't end up using in my rebuild if you need them too..
Leadfoot
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Khal · Posted: Sun Jul 23, 2006 10:15 am Post subject: Re: cam lobes worn down

steeny · Posted: Tue Oct 17, 2006 10:04 am Post subject:

well, i finally got around to getting a mate to have a look at my car on the weekend. He was puzzled as to why a cam would look that bad, then we found the other half of the cam oiler floating in the oil collected in the top of the head.

if you look carefully at the third photo above you can see that the bit over the lobes for 4 is not there. therefore theres no backpressure to fire oil onto all the cam evenly, therefore, number 1 was getting zero oil. looks like someone dropped the cam cover on it when it was put back together. no idea how you could miss that damage

anyway, 400 bucks later i now have a new second hand cam, 2 new followers and a new cam oiler (including the little plastic elbow, so now i have 2

)

all i gots to do is put the bloody thing back together now.
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1978 924 N/A
she's gone.....

Chrenan · Joined: 15 Jan 2003 Posts: 3903 Location: Canada

You may want to think about what could have caused the oiler to snap, otherwise it may just happen again and all the work will be for nothing. How are your engine mounts? When were they last replaced? You could be getting too much vibration with broken mounts.
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1987 951 - M193 Version for Japan

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

^ I would bet someone put their hand on it and rested their weight against while adjusting the valves the last time.

Not much else can cause it to snap off.

Definitely ugly!
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1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet

Chrenan · Joined: 15 Jan 2003 Posts: 3903 Location: Canada

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Don't toss that old cam. . .it can be welded.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

steeny · Posted: Wed Oct 18, 2006 9:33 am Post subject:

theres a little dint in the oiler. given that you have to coax the cam cover in to put it back on, it wouldn't surprise me if the cover itself was smashed against the oiler.

i will have a look at the mounts and stuff as well, just in case.

i wont be chucking the old cam. i'll start looking around for someone who wants to try and get into some sort of better than stock configuration for cheap. at least i will hopefully be able to drive the car while it happens

now all i need is for a cheap rear hatch to pop up somewhere.
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1978 924 N/A
she's gone.....