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Blue Ox

exhaust valve lash

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I have a 2000 ch613 with e7 460. The jake was dropping out so pulled the valve covers to check it out. I  found the exhaust valves had 1/4 inch lash. Adjusted them to .025 and tried to start it. The engine wouldn't fire. Backed the adjustment for the valves back closer to what they were before and it starts but sounds like the jake is on. I have had the truck for about 3 years and had not touched the engine before and don't have any past history on it. Any ideas on what the problem is?

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58 minutes ago, Blue Ox said:

I have a 2000 ch613 with e7 460. The jake was dropping out so pulled the valve covers to check it out. I  found the exhaust valves had 1/4 inch lash. Adjusted them to .025 and tried to start it. The engine wouldn't fire. Backed the adjustment for the valves back closer to what they were before and it starts but sounds like the jake is on. I have had the truck for about 3 years and had not touched the engine before and don't have any past history on it. Any ideas on what the problem is?

you better get a engine manual for that engine, I know the valve lash is real critical with a engine brake.    terry:MackLogo:

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I have the manual and the valve lash is .02 to.028 with the jake.

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😣I SAID IT! F@@ksakes!

 

Edited by fjh

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OK thanks I obviously made a stupid mistake. Not my first probably not my last!

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When I first read this post I cringed, it's so easy to bend and break the valve train parts if you don't adjust that engine exactly right. Won't be the first time!

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Check end of rocker shaft to see if the soft plug came out.If it did it should be laying there.Valve adjustments are marked on flywheel.You can start anywhere just follow firing order from there

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Sorry I was abrasive but follow the directions bring it up to the valve set marks on the flywheel valves on the rock on the opposite cylinder you adjusting 1-6. 5-2 3-4 adjust the valves to 16 intake 24-26 exhaust if it has jakes usually 15 or 22 and as the post above suggest check the rocker shaft for aplugs missing!Hopfully you haven’t ruined it.

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The plugs are still in place. I screwed up the valve adjustment will redo tomorrow, hopefully I didn't break anything. Like I said stupid mistake.

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I deserve the response, I was ignorant. When I am stupid I admit it.

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I do appreciate the responses!

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Your welcome Bud !   Hopefully All goes well!  valve cover usually has the valve adjustments on a  tag on one or the other cover! If ya need help we will try to assist! Or Get mad ! 🙄😁

Edited by fjh

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18 hours ago, brettj3876 said:

Check end of rocker shaft to see if the soft plug came out.If it did it should be laying there.Valve adjustments are marked on flywheel.You can start anywhere just follow firing order from there

Is that common for the freeze plugs to come out.? That happened to me and I ended up drilling them and installing a roll pin. No problem since.

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If you go by the marks on the flywheel say 1/6 that doesnt mean you can set either. 1 or 6 could be on the overlap. If on 1/6 check both cylinders to see which is on the overlap {the valves will be partially opened}. If 1 on overlap do 6  or visa versa.

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If you Go By the marks ( marked)  =  set valves 1-6    5-2     3-4   on the flywheel  and use overlap on the opposite cyi  for checking your self you will be spot on period!

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