4.2l timing

T

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I have a 1989 Wrangler 4.2L. I just installed a Howard cam and a rebuilt 4.2L head that I had milled 60 thousands.
Everything went back together as specified in my Jeep manual. My problem is this: I can't get it timed I put the #1` cylinder at TDC. The distributor pointed to the #1 cylinder, and the harmonic balancer mark was aligned at zero.
I turned the engine over, and after a couple a couple of turns, I would get a noticeable hesitation, and it would turn over again, then repeat. It never started, and started belching fuel out of the weber Carb. What is going on??? Could I have the distributor 180 de3grees out?? I'd sure appreciate some advice. Thanks
 
Like Stoopid said, there are 2 TDC's. One for compression stroke and the other between the exhaust and intake stroke. Sounds like your on the wrong one. BTW with a milled head and other mods you may have to do "by ear" timing. Advance till it pings and retard it back a few degrees for optimum performance.
 
Stoopid Jeep said:
It sounds like your distributor is 180° out. Did you verify that #1 was on TDC COMPRESSION not TDC exhaust?
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I turned the engine over until the distributor was 180 degrees out. There was no noticeable shot of air from the #1 Cyl. I tapped the starter again, and got a large volume of air back at the 180 mark. Turns out I was on #1TDC, but the distributor was so retarded, that I had to pull it and point it to #1 cyl. It finally started, and with some "advance", I was able to get it smoothed out. The "Howard Cam" break-in instructions require two ten minute run in's ,at 2500 RPM, with a break in between to cool the engine. Once I completed that, the engine smoothed out and is now running like it should. Thanks for the helpful information.
Gilaguy23 said:
Like Stoopid said, there are 2 TDC's. One for compression stroke and the other between the exhaust and intake stroke. Sounds like your on the wrong one. BTW with a milled head and other mods you may have to do "by ear" timing. Advance till it pings and retard it back a few degrees for optimum performance.
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Thanks for the information on timing it with a "milled" head. I will fine tune it that way. I do wish "Howard Cam instructions included
what the optimum "advance would be on this cam. So, your advice makes a lot of sense, short of a dyno tune. Appreciate it.
 
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Glad you got it figured out. Lighting off a motor the first time can be frustrating. It's ten times more stressful when there is a brand new cam involved. I hope your break in went perfectly 🖖
 
Stoopid Jeep said:
Glad you got it figured out. Lighting off a motor the first time can be frustrating. It's ten times more stressful when there is a brand new cam involved. I hope your break in went perfectly 🖖
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Thanks. I followed the Howard Cam break in procedure. Two 10 minute run in's at 2500 RPM,, with a cool down interval in between. It went well, and now the engine is easy to start, and smooth running. Now I have to face a new problem. The new throw out bearing, that won't engage on an AX15. It never stops!!
 
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