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Discussion Starter #1 (Edited)
Good evening,

I started this new thread, because the first one was about the crankcase evacuation problem and I guess that there is a double-bug with my engine.

I found out, that the engine is sucking heavy vacuum through the valve covers as I pulled out the evac breathers when the engine is running. The vacuum is increasing when rev up.

When I pull the breathers out of the valve covers, the idle speed increase from 1200 to 2000rpm and when I put my hands on the holes of the valve covers, the idle speed decrease back to 1200rpm.

Does anyone has an idea what can effect this?

Bad intake seal?

Thank you very much in advance

carl
 

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most likely intake leak into the valley,usually they smoke and drink oil as well
 

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Discussion Starter #4 (Edited)
----

no smoke, no higher oil consumption.

i guess i have to lift up the intake. the heads are heavy ported.....





greets
carl
 

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Do you grind through anywhere in the runners? You chopped alot of meat out of the runners and could have hit a leak.
 

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Check the area around the spring seat corners. Had a set that were thin there and only started to come apart (small pin holes) after the engine was run. Did not smoke or seem to lose oil

bg
 

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Discussion Starter #8
yepp, felpro 1206.

I will lift up the intake this weekend to check. hopefully it's just the bad intake gasket and not a problem with the very optimistic porting job.

what makes me thoughtful is the overlay problem. the engine sucks vacuum through the burned out check out valves of the evac system and breathes the hot exhaust gas. :mad:

thanks for all the input.

greets
carl
 

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Discussion Starter #9 (Edited)
update....

good evening,

ich have checked the heads today and found the following:



:mad:

the result of the very optimistic porting. looks like I have to do some work.

greets
carl
 

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Clean it up and weld it or epoxy it.
 

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It looks like that cylinder ate some epoxy! Is there room for some reinforcement on the outside of the port in the valvecover area? JB weld-the original slow set formula would work if there's decent texture and it's clean, very clean.
 

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Or have that pushrod hole sleeved and fill the port area with epoxy, also watch the length on your intake bolts-I see some shiny witness marks on one of your pushrods.
 

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Discussion Starter #13 (Edited)
yes, i recognized that as well. there are 7-8 of these porting leaks that are alredy filled with epoxy. we have filled that leak with epoxy now but I'm looking for a new set of heads.

I guess the heat of the sucked exhaust gas from the bad evac. kit has melted the old epoxy repaired leaks. The breathers were so hot that the filling of them were melted into the valve covers:




there is an opportunity to get a pair of 14 degrees pro-topline new-zealand heads.........just have too sleep a couple of nights about that :).


greets
carl
 
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