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My drz470 started smoking any thoughts

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So my drz470 started smoking blue smoke on start up high revs and aggressive decel yesterday I rebuilt the engine completely 600 miles ago and it's time to adjust the valves. But smoking IMG_1417.JPGis new to me any thoughts

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Ya , intake valve seals .  This is one area I almost always use oem on with few exceptions and lube the crap out of the stem tip when installing .
 
 
.

I actually had to replace the entire head withch is off a 2016 with 200 miles with the valves already installed

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1 hour ago, billyreilly1020 said:


I actually had to replace the entire head withch is off a 2016 with 200 miles with the valves already installed

Then it's not as likely to be the seals , as William said leakdown to see if it's the rings not sealed then .

 

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New rings, good, gaps done 120 degrees apart? Dry or wet (oiled barrel)?

The new piston had marks for the gaps on rings I used assembley lube on the cylinder and everything else I did a complete rebuild crank bearings seal

The new piston had marks for the gaps on rings I used assembley lube on the cylinder and everything else I did a complete rebuild crank bearings seal

Etc.

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9 minutes ago, billyreilly1020 said:


The new piston had marks for the gaps on rings I used assembley lube on the cylinder and everything else I did a complete rebuild crank bearings seal
Etc.

Assembly lube is probably your primary problem. It contains moly and is too slippery to permit proper ring sealing. Only engine oil (dino) or better, completely dry is the preferred method of piston and rings (with just a drop or two of oil on the rob small end). I have never seen marks on a piston to align the rings to. The position of the rings (first set) does not matter but the next set should appx. 120 degrees rotated, then the next another 120 degrees, making all the gaps spaced out.

I'll bet you need to pull the barrel, scrub it with a scotch brite pad, clean 110% and install new rings, circlips and gaskets.

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Assembly lube is probably your primary problem. It contains moly and is too slippery to permit proper ring sealing. Only engine oil (dino) or better, completely dry is the preferred method of piston and rings (with just a drop or two of oil on the rob small end). I have never seen marks on a piston to align the rings to. The position of the rings (first set) does not matter but the next set should appx. 120 degrees rotated, then the next another 120 degrees, making all the gaps spaced out.
I'll bet you need to pull the barrel, scrub it with a scotch brite pad, clean 110% and install new rings, circlips and gaskets.

I'm going to do a leak down test and go from there
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8 hours ago, billyreilly1020 said:


I let it warm up and I did the hard break in method trough out the 600mile

 

8 hours ago, billyreilly1020 said:


New cylinder and piston it started smoking now 600 miles after rebuild

This is a typical break-in for nic-a-sil bores

 

20170709_035833.jpg

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Sorry haven't had time to get back here so I finally did a compression test and leak down test the compression test I did cold and it had 130lbs of compression and the leakdown at top dead center I heard air coming out the airbox and muffler didn't hear anything out of the tranny

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Sorry haven't had time to get back here so I finally did a compression test and leak down test the compression test I did cold and it had 130lbs of compression and the leakdown at top dead center I heard air coming out the airbox and muffler didn't hear anything out of the tranny

Stock or aftermarket exhaust cam?
For reference I have 215 without decompression on a 434. The manual states 130 with stock bore, compression, and cam.

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