Engine/Transmission (1994 - 1998) Cylinder 1 ex valve adj?

[Fordiesel69]

I heard something from a diesel mechanic and not really sure what to think of it. It makes sense though. He told me that when I adjust the valves on the 12v, to leave the cyl 1 ex clearance at 0. 25 instead of 0. 20 because it runs hotter than the rest and it will allow the valve to sit on the seat a tad longer and will extend the life of the valve. Thinking how a valve train works, it does kind of make sense, but is it really necessary?



I did a quick random check of my valves and they are loose at over 0. 25 some are in the 0. 30's. Maybe next weekend I will get around to it.

 

[JoeBioDiesel]

Even if it did make sense, it would scare me a little. I would think leaving the valves a little loose would create more problems than it would solve. It would allow the rocker to slap the top of the valve stem when it opened, and also it would increase the acceleration rates is something that accelerates pretty fast already. It's also "fixing" a problem we don't have. How many guys are burning the #1 exhaust valve?

Joe

 

[Fordiesel69]

Thats why I asked, it did sound good, but on the other hand you would think they would document this in the book somewhere if it really was a problem.

 

[Desperado]

I would also think that it would not be open as long as it should be to release the exhaust gasses.

 

[PToombs]

And it won't open far enough when it does! If the valves are too loose on these engines, they don't start good. Adjust the valves to . 010 and . 020 like the book says.

I think the highly paid engineers at Cummins, who have been building these engines since the mid '80s, are a little smarter than that "diesel mechanic".

 

[Vaughn MacKenzie]

I like mine at . 008" and . 018" & no problems after doing it that way for over 100,000 miles of driving.

 

[Fordiesel69]

I like mine at . 008" and . 018" & no problems after doing it that way for over 100,000 miles of driving.

Why tighter?

 

[Vaughn MacKenzie]

More lift, more flow

 

[Dieseldemon]

I have been setting valves for a lot of my cust and Mackenzie is right more lift and flow . 008 and . 018 or . 009 and . 018 is what I set them at

 

[HEMI®Dart]

I like mine at . 008" and . 018" & no problems after doing it that way for over 100,000 miles of driving.

I have been setting valves for a lot of my cust and Mackenzie is right more lift and flow . 008 and . 018 or . 009 and . 018 is what I set them at

I tried setting the lash like you guys did a few years ago and did not like it at all. The engine had a marked vibration at idle and didn't notice any performance difference. It felt like it had worse throttle response.

 

[Jim Fulmer]

I run mine at . 010 and . 010 but I have piston to valve clearence to do this.



I've heard of . 005 and . 010



Jim