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Cam position issue

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petter View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote petter Quote  Post ReplyReply Direct Link To This Post Topic: Cam position issue
    Posted: Jun/18/2017 at 2:03pm
I bought a Javelin 71 in boxes a few years back here in Sweden,

Due to garage issues and difficulties to get the engine running have the project been taking longer then planned....

Have tried with different distributors, first a standard points one, and a new coil, then i tried with the motorcraft electronic one that i got in one of the boxes and finally i bought a HEI variant but the machine had not a single interest to start......it gets fuel, spark and it has oil pressure while cranking

Yesterday i decided to try to understand whats wrong in detail so lifted the valve covers and cranked the engine.

Then i saw that one of the valve lifters did not move on cylinder 5 (the one to the front), my first guess was that a cam lobe was worn out, a lifter have gone bad or that the lifter had got stuck in top position

Removed the intake to look into it but saw that the lifter was ok and loose....

Put my finger down in the inspection hole to feel the lobe and to my surprise was the lifter resting on a bearing surface and not a lobe.

What have the guy before me done?

For me it feels like he have inserted a totally wrong cam in the engine, i have at least ordered a new cam and lifters and hope that the piston has not hit the valve.....

/Peter
Peter Olsson
Javelin 1971
Saab 9-3 Aero 2008
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401harry View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 401harry Quote  Post ReplyReply Direct Link To This Post Posted: Jun/18/2017 at 2:30pm
Sounds like your timing is out 180 degrees. Timing is checked on cylinder 1 top dead center and that is the first piston to the front on the driver side not number 5. With # 1 at TDC (Check balancer indicator mark) put the distributor back in so the rotor points at the #1 wire terminal and check all your other wires for correct firing order.
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petter View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote petter Quote  Post ReplyReply Direct Link To This Post Posted: Jun/18/2017 at 3:32pm
Originally posted by 401harry 401harry wrote:

Sounds like your timing is out 180 degrees. Timing is checked on cylinder 1 top dead center and that is the first piston to the front on the driver side not number 5. With # 1 at TDC (Check balancer indicator mark) put the distributor back in so the rotor points at the #1 wire terminal and check all your other wires for correct firing order.


Hi Harry

I tried moving it 180 degrees several times last year without any ignitions,
What worries me is what type of cam he had put in the engine as the bearing surface on the cam was aligned with a hydraulic lifter not at the bearing in the block, still the fuel pump and oil pump worked

I assume that its not possible to put in the correct cam in wrong position 1n the block (too far in or out) and still get the stuff to fit
Well.. i will remove the timing chain and pull the cam during next week so lets see what more surprises i find.
Peter Olsson
Javelin 1971
Saab 9-3 Aero 2008
Bmw 528 Touring 1999
Volvo C70 convertible 2001
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one bad rambler View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote one bad rambler Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2017 at 7:40pm
I would pull the front cover and see why the cam is either to far in or out...I would actually pull the cam
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tyrodtom Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2017 at 9:09pm
Are you sure you're not just feeling a completely worn down cam lobe?

The base circle of the cam is pretty close to the same diameter as the bearings.  It is possible that lobe could be worn down to the base circle.   Once you go through the outer hard layer,  the metal underneath will wear pretty fast.   That lifter should be in really bad shape if that lobe is wiped.

If the cam was out of position that much more than one lobe would be of position,  and I don't think there's enough room in the timing cover to let a cam go that much forward,  and there's no way for it to go back that much.

If it was a cam from another engine,  it's hard to believe just one lobe would be out of position.

Is the whole cam turning ?   Cams do break,   if a section broke out,  the rest would free to go back and forth.


Edited by tyrodtom - Jun/20/2017 at 9:21pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amc67rogue Quote  Post ReplyReply Direct Link To This Post Posted: Jun/21/2017 at 2:02pm
Is it a new rebuild? So does the lifter on # 5 EX. valve sit higher than the rest of the lifters ??
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petter View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote petter Quote  Post ReplyReply Direct Link To This Post Posted: Jun/21/2017 at 4:34pm
Its is a "newly" rebuilt motor by the previous owner.
He claimed that it has started, but now i do not believe him about that....

The valve that where on the bearing was under pressure but no movement at all, the lifter is also in a high position that wa why my first assumption was that the lifter was stuck in the block
I have ordered a new cam and lifters, will post some pictures when i have the cam out and when i get the new cam from the states (takes 2 weeks to Sweden)

Peter Olsson
Javelin 1971
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Bmw 528 Touring 1999
Volvo C70 convertible 2001
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amc67rogue Quote  Post ReplyReply Direct Link To This Post Posted: Jun/21/2017 at 8:18pm
With that lifter out try to LOOK down into the bore. You're looking to see if it is the cam journal or the OD of the #3 cam bearing. IIRC there was a post on this forum about #3 cam journal being to long.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Zioamc Quote  Post ReplyReply Direct Link To This Post Posted: Jun/21/2017 at 9:32pm
cam plug at rear of block might be in to far or maybe there are two in there
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tyrodtom Quote  Post ReplyReply Direct Link To This Post Posted: Jun/21/2017 at 10:34pm
When I went out and looked at a AMC camshaft in my garage,  I realized how stupid part of what I suggested was,  there's no way you could mistake a cam lobe, for a cam bearing.

But the cam would have to either be back almost 1/2 inch,   or that would have to be a very wide cam bearing.
66 American SW, 66 American 2dr, 82 J10, 70 Hornet, Pound, Va.
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