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 Posted: 08-03-2005 02:15 pm
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Ron Earp
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My 74 JH seems to have come with a single grove crank pulley and four timing marks on the front cover. I assume them stock.

But, Mark emailed me and reminded me that if this type of pulley is placed on a newer engine the timing will be 10 degrees off. And, if the timing was 10 degrees off, well, wouldn't that make setting the valve timing up difficult? just wondering as I am having difficulty starting mine. Ignition timing seems right, valve timing was right, but she coughs and spits out of both ends telling me the engine is not timed right.....

What serial number engines did this switch take place on?My car is a 74, will check engine number.

I've got to do more investigation, it could be it jumped time (ignition or valve timing) on the first few cranks and it now badly out of sorts.

Ron

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 Posted: 08-03-2005 02:40 pm
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Jensen Healey
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I had a similar problem after my rebuild.  Turns out I was thinking backwards about the distributor rotation and the wires were wrong. I was embarrased but happy it was a simple fix.

The check valve on the brake servo was blown out during repeated attempts to start the engine with bad timing and the servo required a rebuild.

Good luck,

Kurt

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 Posted: 08-03-2005 06:45 pm
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Brian Kelly
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Ron,

One other thing and sorry if I’m stating the obvious but……

When setting the ignition timing statically make sure to rotate the distributor in the opposite direction than the dizzy rotates so that the #1 wire distributor cap contact contacts the leading edge of the rotor first.  If the cap is turned in the opposite direction it will contact the trailing edge of the rotor resulting in your timing being off by another 20 or so degrees BTDC.

It’s a mistake I made!

Brian

 

BTW I’ve got extra parts you’ll be interested in but I just haven’t been able to bring myself to part with them yet.  My little 2 car garage is bursting at the seams now with the addition of the TRV so some of this stuff eventually will have to go. Also I’ve been swamped with other cabinet projects.  Too little time!!!

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 Posted: 08-03-2005 06:45 pm
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Brian Kelly
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Last edited on 08-03-2005 06:46 pm by Brian Kelly

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 Posted: 08-03-2005 07:51 pm
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Ron Earp
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Well, here is what sort of started all of this - troubles starting.

Right now when you crank the engine she spits out of both ends - carb and exhaust. 

The cam timing is dead on at 110 In 110 Ex.  I also know that when the timing pointer is at zero the #1 piston is at TDC, verified that when I built it with a dial indicator.

The ignition timing is right, we've checked and double checked that, it sits right at 9 degrees before TDC.

But, still spits out of both ends.

Leak down test reveals that #1 and #4 are leaking down a lot, probably through the valves.  Clearances were checked, spot on. But dammit, the head was just rebuilt and should not have bent valves since the timing was dead on, and shouldn't have sticky valves either - still, we've got some leaking going on.

So, I'm pulling the cam carriers, taking the cams out of the equation, and doing a leak down. If the problem goes away, we know it is the cams/timing for some unknown reason.  If it stays, then I suppose we've a head problem.  I'm just perplexed since before I put the head on it had a three angle valve job and I put WD40 in the combustion chambers, turned the head upside down, and let it sit overnight - no seepage or leakage.

I'm starting to suspect something funny with the cams, cam gears, and cam timing, but I can't seem to figure it out since it all seems right.

Ron 

 

Last edited on 08-04-2005 12:58 am by Ron Earp

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