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Discussion Starter · #1 ·
My wrench had my heads pulled and recommended lapping the valves, as they werent sealing properly...(poor work done by Branch)..anyway, the jugs were honed at the same time, new rings installed. The guy that worked on the heads put new valve guide seals in..teflon.

I have put about 700 miles on the motor so far...it's running very strong only problem is, there is some oil consumption. I expected a little for break in but i'm not sure this is right.

I get oily soot build up on my front cylinder exhaust pipe ant the plug has oily soot as well on it. The rear is clean. I'm thinking it's the valve guide seal on the exhaust side, both cylinders pump up to 200 lbs even..

any thoughts?

Tom
 

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If it is a leaking valve seal I would guess the intake since you have signs of oil on the plug. If it leaked in the exhaust it would likely go out the exhaust and not back into the combustion chamber.
 

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Discussion Starter · #3 · (Edited)
I dont notice any smoke coming out the back...

I'll let it go for probably another 300 miles and bring it back to them.

If i took a pic of the plug would that help any diagnosis?
 

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A leak down test may tell you exactly where the leak is...it helped me find the cause of a similar problem...
 

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Discussion Starter · #5 ·
A leak down test may tell you exactly where the leak is...it helped me find the cause of a similar problem...
will a leak down test find a bad valve guide seal?
 

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Discussion Starter · #8 ·
How are you venting the heads?

You may have to pull the front head. You have run 700 miles already-don't see how another 300 is going to change anything.
the only venting I know of is the SE a/c installed..Is that what you mean?

The 300 miles is just to prove to the wrench that it 's puking a little oil out the pipe.

T
 

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Have you noticed that the pipe only pukes oil after longer rides, but not after shorter rides aroud town? If so, this happened to me and we initially thought it was the guide but it turned out to be a poor return of oil/pressure issue. Pressure kept building up in front head and needed a place to go. Eventually after longer rides it would blow some out the front pipe. Wouldnt notice it around town as the short trips allowed the oil to slowly drain down.

Not familiar with the Branch Head design. Maybe someone familiar with Branch Heads can chime in.
 

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Putting new rings on old pistons can fail sometimes, not often but it can fail we have seen it happen. One of the cylinders does not seal the results is oiling or wet cylinder the oil in the cylinder never dries gas does. What grit stones did you use when honing the cylinders and did you hone cylinders when you re-ringed it.My guess is its piston or ring related a leak down test will not show loss of oil contol to the oil rings.
 

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look at the plug, it aint rings. and it aint because branch (mikuni) did the heads. i think pmorris hit it with poor drainback, insert shitty seal and maybe guide. think about a set of heads that required lapping valves-------------enuff miles to require guides and seals?? question is, why didnt mechanic inspect and repair?
 

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Discussion Starter · #13 ·
look at the plug, it aint rings. and it aint because branch (mikuni) did the heads. i think pmorris hit it with poor drainback, insert shitty seal and maybe guide. think about a set of heads that required lapping valves-------------enuff miles to require guides and seals?? question is, why didnt mechanic inspect and repair?

The story behind that is, at around 12k miles, I had the work done on this motor by a local indy.This included new cams, Branch machine work on the heads, hi volume oil pump, lifters, and a few other things. When he was done, the motor was making a tapping noise...the indy that did the work, put a few more hours looking for the noise only after I told him it didnt sound right, and he agreed it wasnt right...he gave up working on the build, as he couldn't find the noise and didn't want to spend anymore time and energy fixing his fk-up...told me to get the POS out of his shop. Nice guy. I put maybe 1200 miles on it before the noise just drove me up the wall. I took it to another builder...paying him to find the noise. we pulled the pump...went back to stock, changed out lifters, push rods.

Checked the cams. couldnt find noise. Decided to check the top end. The heads were pulled to determine if there was any problem with it or the wristpins on the pistons. The heads were sent to a machine shop in Hayward that does head work. The heads were put on a flow bench to test vacuum. Couldn't get a seal.... on any valve, he lapped them...got a good seal. He put new valve guide seals. The machinist also asked if he could have the jugs to check them out as well. They were ok, but since the were out, he honed them and had new rings installed. Put the motor back together, comp test...200 lbs each hole. Decel pop has been minimized..great compression, but the noise is still there, which is directing us back to the cams again.Come springtime, gear drive cam swap.

I dont know what is causing the oil consumption...the wrench is going to pull the head again and check the guides and rings.

pmorris mentioned poor oil drain back....what would cause that. I didn't have the oil problem before the the latest round of work, so I dont know what was done that would change anything oil related.

claydbal, there are only 2k miles on these Branch heads...for a shop that specializes in performance head work, I think their work was piss poor...those heads should never have left their shop in that condition. I would have had them returned to Branch to repair their work, but it was the original indy that had the work done...and you know how he stands behind his work....tail light warranty.
:beatdh:

Thanks fer listenin' to my rant.

T
 

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gee man, i hope you get straightened out this winter. branch sold to mikuni, so you aint really getting jerry branchs hand work. the rocker box gasket can be installed backward, which blocks the hole is what i think pwmorris referred to???? did you see the seals? guides? guides can crack and also crack head beside the guide! and seals get damaged during install if not done correctly.

it may behoove you to pull motor and ship it to someone you can really trust. beats tossing money in that hole another year.
 

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Discussion Starter · #16 ·
i talked to my (current) wrench, and he has no problem cracking it back open...on his dime, to fix the oil prob.

I'm learning about the trust thing....I cant even trust the local dealer here to do whats right....thats a whole nother story in itself..:thumbsdn:
 
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