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Discussion Starter · #1 ·
So I am hoping someone can tell me what is going on. Lets start from the beginning. I have built basically a 7A-3B, 034 IIB. I had an issue with the engine and could never figure out what was wrong was only running on two cylinders and smoking like crazy, there was a few problems (Tyson helped sort through, thanks buddy). It came down to 2/3rds of my hydraulic lifters had collapsed and was not allowing a/f mixture. I promptly ordered lightweight new ones from 034 and they were shipped right out. I had pulled the cams (7A's on 7A head) and cleaned them up. re-lubed and re installed into the cylinder head. I had put her back together and the moment of truth wham not firing in fact sounded like it was free wheeling. what do you know it was broken which means what gentlemen? Bent valves. (F-WORD) luckily enough I had picked up an excellent condition long block and I began pulling cylinder heads. Got it all put back together and ping, another cam gear key luckily I had smartened up and rotated it by hand (crank bolt) to make sure nothing slipped. I rotated it about 6 times and noticed the timing on the cams was no longer aligned. F%$%^&K! another cam gear key. So finally I ran Edmonton dry of 7A and AAN cam gears and got a AAN and promptly removed the trigger wheel. I got it all set up and rotated it about 20 times to make sure nothing moved. Success and I finish assembly and try to fire the beast up. nothing.......... GRRRRRRRRRRRRRR checked compression NOTHING! so I feared the worst an *((*&*(&)(*& cam key broken, might have toasted a perfectly good head.

Why are the keys breaking? and how can I check if the valves are bent without pulling the head (doubled up MLS gaskets get expensive when you have two for dropping compression.)

please help! :frustrated: :frustrated: :frustrated: :frustrated: :frustrated: :frustrated: :frustrated:
 

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keys themselves actually breaking? a separate key from the pulley, shearing? I have heard of the pulleys breaking. please show some actual pics of broken stuff.
 

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How are you holding the cam pulley when you torque the bolt? The key on the 20v pulleys is really fragile. Too bad no one makes a billet replacement without having to be all adjustable and not fitting under the timing belt cover. A good machine shop should be able to cut a slot in the stock pulley and make a separate hardened woodruff key which would be much better than the stock powdered metal.
 

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How about this? are you getting the cam caps back on in the right orientation? if you put them on backwards they will bind the cams and make them very hard to turn, thus shearing the keyway. Did that once on a 16v motor... never again....

according to the repair guidelines, the notches go towards the intake.
 

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Discussion Starter · #5 ·
I am following the service guide install guidelines.

it says 11ft lbs on cam torque order from the bible, 48 lbs on cam gear (torqued in vice with wood and rags to protect) then installed back in and I checked all of the timing marks repeatedly and double checked WHILE rotating with valve cover off, crank, cam (circles) and rear mark on timing gear. when I start to time it I take out spark plug 1 and put a large screwdriver in to see when it stops at TDC before hooking up the cams.

I have been VERY meticulous about making sure the timing is correct. Timing belt is able to be turned with moderate force with thumb and index to 1/4 turn and water pump retorqued to factory specs. This is why I am confused. There is NO reason this should be happening and everyone I discuss this with is stumped.

The cam caps are being taken out and laid in order/orientation and putting back in the right order (standing on intake side) numbers are right side up for reading.

this is why I am SOOOOOOOOO confused. it ran/rotated fine before changing the lifters.
 

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Discussion Starter · #6 ·
oh and the cam key is part of the gear
 

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So you're holding the cam or just the pulley in the vise when torquing the bolt? Then you're installing it in the head? How on earth are you getting the cam seal in then? You should be tightening the cam bolt with the cams installed in the head while holding the cam pulley with a counter holder.
 

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people break these things a lot it seems. I would only hold the outside of the pulley since that is how it is designed to take the force. That way, the force is transmitted through all spokes, if somebody uses a screw driver or whatever through the spokes all the force is concentrated on one spoke and the powdered metal breaks. *probably*
 

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Discussion Starter · #10 ·
I slide the seal on before the gear goes on and if you hold the camshaft in the vise (protected) it will not move. then no force is required on the gear at all.

I went and raided all the 16v VW gears from the wreckers and retorqued all the caps with a lower ft lb wrench and it seems to be holding, good compression all across the board. (which I didn't have before) I am just charging the battery. Fingers crossed!!!!!
 
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