The Travesty of it all...


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CopperCollar
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The Travesty of it all...

Post by CopperCollar »

Been busy, changed everything ignition related yesteday with known good parts yet the problems still persist. I had a miss that was most pronounced when warm and at 5500 rpm, engine was sluggish from there on but otherwise pulled strong up to 5500rpm.

Today I warmed the Travesty up and ran leakdown test,again not good. 20% from each cylinder and I could hear air escape from the cam chain tunnel.

I noted some air leak from #5 intake.

I used NPR rings, honed the cylinders everything spec'd within limits before I assembled the cylinders.

Since #5 was leaking some air through the intake I decided to pull the valve cover and check the clearance.

Well I found four of these in the oil pockets. They measure 4-6mm and are hard like ceramic.
Image
Image
Image

I can only assume some of these got past the valves, into the cylinders and wracked havoc there thus the poor leak down test and possibly a bent intake valve.

I can only assume this is the shot media the machine shop used on the head. I specifically stated no bead blasting but when I picked the head up ...well it was to late. Knowing this I really worked hard at cleaning the head, used hot soapy water, bottle brushes and pressure washer.

I think this is a very good example of why engines should not be bead/shot blasted.

Looks like I'll be pulling the engine down.

Bummer
When given the choice between being right or being kind; choose kindness. W. Dyer

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Kool_Biker
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Re: The Travesty of it all...

Post by Kool_Biker »

Bummer indeed CopperCollar
Can you VERIFY (contact the shop) that the little balls are remnants of the blasting process before you go any further?

Hope all goes well and damage is minimal.

Aris
Aris Hadjiaslanis
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steve murdoch icoa #5322
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Re: The Travesty of it all...

Post by steve murdoch icoa #5322 »

Any of the media that i have seen has been much smaller.
Hang in there Mike, this will just make the end result more rewarding.

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CopperCollar
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Re: The Travesty of it all...

Post by CopperCollar »

I'll drop by later and ask. We used this big media when blasting oil field tanks. Not sure what it is yet so I'll be cautious in my query. I have nothing like this in my shop. Work bench was clean during engine assembly.

So far I have found no more of the little gremlins.

Going to drop the pan and filter if that is clean I'll run the valves and button her up. Then warm her yup for a hooky compression test.....20% leakdown means little To me until I have the compression check numbers.

She runs good until hot, then I get a miss at 5500 and sluggish pull from there on. I wouldn't have found this if I hadn't decided to run a leakdown and check the valve train.....

So I muddied the real issue, the 5500 rpm miss which is more likely to be ignition more than mechanical.

I figure the rings will seat in. and improve the leakdown. Butt I really need to get the compression test fine and tie the two together..

Mike
When given the choice between being right or being kind; choose kindness. W. Dyer

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CopperCollar
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Re: The Travesty of it all...

Post by CopperCollar »

Well I think I have stumbled into the potential cause of my issues.

Whilst the Travesty cranks up fine and idles fine in retrospect she really always ran a little lumpy compared to my 79.

I warmed her up today and attempted to balance the carbs but the base carb..that being #4 would barely pull 10 cmhg at idle. She continued to be a bear to balance out and idle returned to baseline slowly.

Going through my head there was a few issues that could cause the low manifold vacum but it was cam timing that most intrigued me.

Whilst they looked right I believe I failed to assure that the timing dimples of the intake and exhaust sprockets were in the same plane. They looked aligned with the cylinder head but I did not really look to see if they both were in the same plane so it is concievable that one cam is retarded and one timed correctly or even advanced a tooth.

Tomorrow the valve cover will come off again.....

Are we having fun yet???

Mike
When given the choice between being right or being kind; choose kindness. W. Dyer

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Re: The Travesty of it all...

Post by Kool_Biker »

CopperCollar wrote:I'll drop by later and ask. We used this big media when blasting oil field tanks. Not sure what it is yet so I'll be cautious in my query. I have nothing like this in my shop. Work bench was clean during engine assembly.

So far I have found no more of the little gremlins.

Going to drop the pan and filter if that is clean I'll run the valves and button her up.

Mike
Any news re those mysterious blasting balls?
Have you gotten to the bottom of THIS problem? How clean was the pan / oil filter ?

Aris
Aris Hadjiaslanis
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Re: The Travesty of it all...

Post by CopperCollar »

Hey Aris,

Nothing on the ceramic balls, I haven't been to the machine shop yet.

Oil pan was very clean as was the filter.

Hot compression test was 120 on every cylinder, low but even. The low compression, lumpy running along with low manifold vacum leads me to believe cams are not timed correctly.

Mike
When given the choice between being right or being kind; choose kindness. W. Dyer

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Re: The Travesty of it all...

Post by Kool_Biker »

Mike, if you know ANYTHING about my perils in this forum with shot blasting, you will begin to realise how glad I am your pan and filter are clean and free from debris :laughing-rollingyellow: :laughing-rollingyellow:
Make sure all of these 'balls' are found and removed, and you do not end up with a very expensive shot grinder like me!!!

Regarding the above cams timing issue, I am sure there are infinitely more qualified people who will jump in to advise.

Best
Aris
Aris Hadjiaslanis
ICOA # 6309
Berkshire, Windsor

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CopperCollar
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Re: The Travesty of it all...

Post by CopperCollar »

Have had a lot of detractors from work and home but I am back on track again.

I pulled the top end off all looks good. I flipped the head over and filled the combustion chambers with water 24 hours and no leakge so I think I can rule out any valve leakage.

The NPR rings, I can't point a finger at them either. I can only blame my self for cutting a corner. I felt the cylinders were good, taper min and no ridge, piston to cylinder wall clearance was within limits.

Thought I could get by with a good honing. I can say no now.

Compression never got better than 110psi, leakdown never improved and I could hear air blowby from the oil fill hole so I figure my problems were piston/ring blowby.

Piston ring end gap at the cylinder base was wnl but near the top where the ring shuttles they were consistently .50-.55mm Way out of spec.

I had not checked that earlier....my bad.

So I am waiting on a big bore kit from Chiba Japan then I'll have Preston bore out the cylinders and fit the Big Bore kit....something I should have done in the first place.

Soon the Travesty will be back together....none the less I have enjoyed every minute of wrenching.

Mike
When given the choice between being right or being kind; choose kindness. W. Dyer

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