How to flush out a new build

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RockinRobin

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I had my race motor rebuilt. Apparently the machine shop the builder used did not boil the block. Now it loses oil pressure because the pickup screen keeps getting clogged with gunk. I backflushed the pickup tube and it restored normal oil pressure for a while, that's how I know. There are NO spun bearings! No metal shavings in the oil, just gunk.
Is there a way to clean out the oil passages without disassembling the motor?
Flushing crankcase with diesel?
Other suggestions? Taking it back to the builder is not an option.
:-(
 
Total dissambly is ur only way to go. Don’t forget the oil pump gets unfiltered oil. All the gunk is getting circulated thru the bearings and getting into all the nooks and crannys. U will need to change all bearings at a minimum. I would get the block hot tanked. Kim
 
First run cleaning taps through all the threaded holes. Then remove every plug, scrub every passage with Tide and hot water using a new engine brush kit. Rinse and repeat until the brushes come out clean. Then blow compressed air through all passages until no water comes out. I like to finish up with some WD40 before I replace all the plugs.
 
Thats the first thing i do when i get a block back from the machinest is run engine cleaning brushes thru it and flush it out. Even if the machine shop says they cleaned it, you are the last line of defense before it goes together.
 
Hard to believe a machine shop wouldn't hot tank a block before machining. That's the first step. If you miss that step, you have to start at square 1 again
Find a good machine shop
 
Look around the greater Austin area, visit the machine shops & ask lots of questions. Disassemble, have them hot tank the block, take it home, clean all passages with Tide & brushes. Tap all threaded holes, run hot water into the passages until clear. Spray with liberal amounts of WD40, hone the cylinders, reassemble.
 
UPDATE: Car has been at the body shop and hasn't been started in 6 weeks. I started it up today and it showed 55psi oil pressure. WTF??
 
almost certainly all the gunk has dropped away from the pickup screen while it's been sat at the bodyshop. it will block again.
Sounds like if I drain the oil and blow air backwards through the pickup, then run an engine flush through it I might be able to use it again. I have to remove the engine to drop the pan, trying to avoid that.
 
UPDATE: Good news! I am officially an idiot! Well, you knew that already. It turns out I had the in and out oil lines reversed on the remote oil filter. Switched them and I now have 75psi at idle (1400rpm) and 85psi at 3500 which is all the higher I took it so far. Why so high? It's a racing motor with a HP oil pump. :BangHead::thumbsup:
 
UPDATE: Good news! I am officially an idiot! Well, you knew that already. It turns out I had the in and out oil lines reversed on the remote oil filter. Switched them and I now have 75psi at idle (1400rpm) and 85psi at 3500 which is all the higher I took it so far. Why so high? It's a racing motor with a HP oil pump. :BangHead::thumbsup:
10 sacks with a wet noodle!

Glad it’s up and running.
 
back washed the filter. yuk...well you can reuse it now, it's clean :rolleyes:
 
Thats the first thing i do when i get a block back from the machinest is run engine cleaning brushes thru it and flush it out. Even if the machine shop says they cleaned it, you are the last line of defense before it goes together.
Maistrelli why do you disagree with that statement? I subscribe to the thought process that YOU as the end assembler of it are the LAST line of defense ! I work in the aviation industry. I take NOTHING for granted when putting something together. Oh it's the other guys job to do this or that doesnt cut it in aviation mtx. That's real expensive stuff that can kill people if it fails. If your building something like a car engine that's high dollar money for you, which by the way is still a drop in the bucket compared to aircraft parts, then you should be taking the same care to make sure its antiseptically clean before reassembly.
 
Maistrelli why do you disagree with that statement? I subscribe to the thought process that YOU as the end assembler of it are the LAST line of defense ! I work in the aviation industry. I take NOTHING for granted when putting something together. Oh it's the other guys job to do this or that doesnt cut it in aviation mtx. That's real expensive stuff that can kill people if it fails. If your building something like a car engine that's high dollar money for you, which by the way is still a drop in the bucket compared to aircraft parts, then you should be taking the same care to make sure its antiseptically clean before reassembly.

I've had about a teaspoon worth of metal grit and shavings come out of a freshly machined block that is supposedly "100% clean, ready to go". I almost believed him and assembled it, but my OCD took over and I had to be sure. I'll never skip it, no matter what they say.
 
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