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Engine Noisy When Hot - Exhaust Manifold Gasket?


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Rockers may be too tight and holding the valves open. Before you pull it apart, try a spoonful of fresh gas in the throttlebody and see if it tries to fire up.

Rockers can't be too tight. They're torqued down to zero lash, not adjusted to zero lash.

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Rockers may be too tight and holding the valves open. Before you pull it apart, try a spoonful of fresh gas in the throttlebody and see if it tries to fire up.

Rockers can't be too tight. They're torqued down to zero lash, not adjusted to zero lash.

 

I'm wondering what he bumped (now that we know it's no spark) C101 connector? TPS  unplugged?

Is this the same one making a knocking noise from the dist area?

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It's a stretch, but the last time I had my valve cover off, I must have somehow leaned on the distributor cap and cracked it badly enough to push a terminal down into the path of the rotor. When I went to start it, it cracked the rotor. After searching for this and that, I noticed the cap was cracked, took it off and was able to spin the rotor by hand. Replaced rotor and cap and she fired. I know it's a long shot, but look at your cap and rotor.

 

Good Luck.

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Cruiser, I'm getting fuel through the cylinders.  Plugs are wet with gas whenever I have pulled them.

 

I was able to get a friend over here to help me out and found that the coil is outputting, but the spark looks weak.  Its very thin and orange in color.  I'm hoping the problem is the coil is not outputting a strong enough spark to get through the distributor, plug wires and plugs.  I have a line on one about a half hour away so I'm going to go out and get it shortly.

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The coil was causing the no-start condition.

 

Its very strange that I was getting a low reading on the CPS though.

 

In other news, while there valve train might be marginally quieter, there is a louder tick coming from what seems to be the front cylinder.  This tick was there prior to me changing the rocker arms and now it is worse.

 

With a screw driver on the valve cover, I can feel the knock/tick (whatever you want to call it).  When I put the screwdriver on the head, the knock/tick is barely noticeable.

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Re. increasing CPS voltage...getting it closer to the flywheel.

 

I don't think its carbon buildup, though it is possible.  I have run a few bottles of seafoam and techron through the fuel system since I owned the truck.

 

This is a very audible/noticeable/distinguishable knocking coming from the valve train at the front cylinder.  Its almost like the rocker arm is hitting the valve cover.

 

It may very well be a collapsed lifter or something.  But I'm not yet convinced its worth pulling the head off this motor.

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Re. increasing CPS voltage...getting it closer to the flywheel.

 

I don't think its carbon buildup, though it is possible.  I have run a few bottles of seafoam and techron through the fuel system since I owned the truck.

 

This is a very audible/noticeable/distinguishable knocking coming from the valve train at the front cylinder.  Its almost like the rocker arm is hitting the valve cover.

 

It may very well be a collapsed lifter or something.  But I'm not yet convinced its worth pulling the head off this motor.

Some MMO or Restore in the crankcase can easily clean up a lifter.

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The valve cover and valve train is sludge free. When I pulled the valve cover, I was pleasantly surprised. But seriously, there wasn't a bit of sludge or build up any where.

 

The engine was (allegedly) "rebuilt" by the PO about 4k mikes ago with a 97 xj block with 80 something thousand miles. The original head was cleaned and reused. That's when he put in all the performance internals.

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  • 3 weeks later...

Update: the valve train noise has not gotten any better and I have put another 400 miles or so on the truck.  If anything, since I installed the new rocker arms, the ticking at the front cylinder has gotten worse.

 

I'm at a loss...

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First, pull the valve cover and run the motor and see if that rocker is pumping oil. If not, rap the rocker on the pushrod side (straight down in line with the rod) and see if the oil starts coming up (make sure the pushrod isn't clogged first) Mine does that about every 5th oil change and I add a can of CD2 engine oil detergent and it goes away.

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