LegendsRacer - Legends & Bandolero Racing Forum
LEGENDS => Engine Care & Tuning => Topic started by: JGRacing on June 22, 2008, 10:00:51 pm
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I finally got my engine running and its smoking out of the exhaust like crazy when it gets up to temp (or what I think is up to temp because the oil temp gauge evidently does not work >:( ). I have a temp gun and the case is around 200 degees when the smoke starts. No smoke until it is going for a few minutes then it starts smoking. I paid the place I got it from $1500 to have the head done but it is looking like a valve seal or something. I don't think it is rings or a bent valve because the compression is 190 to 200 lbs on all cylinders even with the cams turned back. It looks like the heads were decked a little too much. >:( To say I am ticked would be a big understatement. Any thoughts on where I need to start?
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Just had a thought. If the muffler has oil in it from the previous motor it was on, could that be why I don't see smoking until the engine is hot? I would think that as soon as the exhaust gets hot (first minute or so) that it would smoke, but just trying to figure out what the issue might be.
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Oil in the muffler should burn off fairly quickly and then be done. Take the muffler off and see if it smokes that will tell you for sure.
Did you over fill the engine with oil?
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Oil is about 3/4th of the way up the window on the front of the motor when it is hot so I think the level is OK. It's strange how it goes from no smoke to smoke just pouring out. I've run it 3 or 4 times for about 5 to 7 minutes each. I tried giving it a little gas (about 5000 RPM's) when it was at temp to see if it would clear out the cylinders, and it didn't help.
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Did the head or head gasket get put on wrong?
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A legends dealer assembled it so not sure.
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What exactly was done to the head/engine. I will not do a "valve job" on an engine. I have people send me heads for the job, but I will not do one on an engine myself. Alot of times when the upper end of the engine is rebuild, it amplies the wear in the pistons/cylinders/rings. I did a couple of valve jobs years ago and those engines all had smoking issues when hot. Based on your compression numbers, it might very well be a lower end issue. The compression will be high due to the fact the oil is getting past the oil control ring and aiding in the top & second ring seal. You might take off the muffler and see if it is one cylinder or all four.
In regards to deck height: The deck height was probably only machine until it was flat, but if it has been machined several times prior it is getting pretty short.
Let me know if I can be of further assistance.
Randy - RPM
rpm@swaybar.com
Thanks,
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I'll pull the muffler and see if it is one cylinder. Also going to try a leakdown test. I talked to the dealer and the engine was run in after the head was rebuilt (not sure of the specifics beyond new springs and decking) and they did not have any issues. When I picked up the car in January the old fuel cell was already out and I did not run it until last weekend. The plugs look a little wet but no fouling (not sure if synthetic oil would foul). Unfortunately, the nearest engine builder who handles legends cars is hundreds of miles away and none of the local bike dealers want anything to do with an engine that is not in a bike. Hate to spend the money to ship it somewhere only to find out that I can't afford the repair bill at the moment.
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Randy,
Should the leakdown test be done with the engine hot or cold if the oil might be sealing the rings?
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Check it cold as that will give you a worst case senario.
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I would check it hot. jmho.
My reasoning: the oil is thinner at temp.
Your temp gun is a starting point; But remember that the case helps dissapate heat. It is not the most effective way to test oil temp. Try to get your gauge fixed so that you have a little bit more accurate reading. Maybe a cooking thermometer dipped into the oil would be of some help. ??? Just a thought.
Is there oil in your exhaust system? Are you running air cooled or water cooled? Gasket put on wrong? (Could Happen) Any results from pulling the exhaust?
Just throwing out my random thoughts. Hope you get it figured out soon.
Steve
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Engines typically seal better when hot because the pistons and rings expand. It wouldnt hurt to check it cold then warm it up and check it. If you check it cold you should know right away if its bad or good.
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Ok; I understand your reasoning.
Checking hot and cold may be of some help. :-\
Steve
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Its really hard to diagnose engine issues online. I would say have a fellow racer look at it or bring it back to the dealer and have them look at it since you said it was fine before they worked on it.
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Problem is that the dealer is 6 hours away and there are not any other legends racers within hours of me. They said that it was run after the head work and they did not see smoke. I'll see what information I can pull together and go from there. Thanks everyone for the advice. Hopefully I will actually get to race at some point.
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Another thought...
OK, they say they ran the engine - no smoke.
Did they run it up to temp, or just fire it up and say yep it runs? ???
Steve
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They said that it was up to temp.
Last night I tried my new leakdown tester and evidently it is defective. It only reads 25% no matter what I do with it (including putting my finger on the end of the hose or just leaving the hose open). My garage has a curse on it. When I was trying it, one cylinder made a small popping noise at about 30 PSI and then was really hissing air into the crank case. The other 3 hissed but not as loud. I pulled the headers and had soot in all the the exhaust runners and oil on one of them. Did not see oil in the muffler. I'll try the replacement leakdown tester, but I think that this may have gotten beyond my small engine skill level. Guess I will be shipping it off to someone. I checked in with some of the local dwarf racers and they did not have any buildings within a couple hours of St. Louis.
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If you can hear air coming out of the crankase breather I would think you have a ring issue or hole/crack in a piston. Did the oil in the header tube match the cylinder that was leaking a lot?
Make sure you read teh directions on how to set the leak down gauge if you havent used one before. They can be tricky and can very easily be set and used wrong.
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You may want to look into a new motor if your old one needs rebuilding. With the new trade in policy that 600 Racing is offering you may be able to get a new sealed motor for about the same price as a rebuild. 600 Midwest has a few in stock (I don't work for them). There website is www.Koiltour.com
Bob Johnson
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I ran it with just the open headers and the front cylinder was smoking the most. I did notice that the header pipe is loose in the sleeve that goes into the head so not sure if that could be making it worse. The collar holds the sleeve in but the pipe is still a little loose. Not sure if it is welded or a press fit.
The second gauge on the replacement leakdown tester jams ($30 from Harbor Freight), so I'm going to just replace it with a decent gauge. Still cheaper than buying one somewhere else.
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Look to make sure the gasket is there. Have you checked the valve clearances. How about one of the valve seals come loose. Call Hank Scott and ask him if he has any advice for your problem. He helped me out with low compression problem.My valves were way out of adjustment.
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Sounds like rings to me, especilly if the compression is 200 not good, leakdown is a must it will tell you what you need to know, keep us informed.
Mike.
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It's at the shop this week, so hope to have some answers soon. I'd drop a weed eater motor in at this point just so I could get on the race track.
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Did you get an answer on the smoking problem?
Randy - RPM
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Hi Randy,
I've been keeping track of this thread. At last report, still no word from his engine builder.
Steve
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Still waiting to here back on the engine. Hoping to get this resolved soon so that I can get in a little racing this year.
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Looks like the cylinders and rings are worn out. They are also taking a look at the bearings since I found some some chips in the oil filter screen. When I pulled the screen a few weeks ago at night covered with thick oil it looked OK, but after the oil draining off for weeks and in daylight I noticed some copper looking slivers. Hopefully the parts will be in this week.
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At this point, You might as well go ahead and have bearings and all done. They already have your engine apart. JUST DO IT!!!
You pretty much missed the season anyway.
Steve
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Did they steal your engine? Or are you going to get it back sometime soon?
If I keep waiting. I may die of old age. :P
;D
Steve
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This week, hopefully.