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Old 12-17-2008, 07:22 PM   #46
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Thanks for the reply's.

I put a new p3 in it when i put it back into my buggy, but i will try a new one again to be sure.
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Old 12-18-2008, 09:43 AM   #47
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Originally Posted by jpalessi View Post
I would try a new OS p3 plug, and make sure your glow ignitor is fully charged. Sounds to me like a weak glow.. Our Glow Plugs will only carry the glow from the original spark from your ignitor. So a weak ignitor = a weak glow. Most ppl believe that as long as it starts, it's all good, and that's just not the case. The glow WILL NOT get better during combustion. Good Luck!
Good info! I never knew that about the glow not getting hotter as it runs
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Old 12-19-2008, 12:23 AM   #48
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Well i don't know WTF is wrong with this engine.

I took the hole engine apart cleaned it(piston has been in the correct way and no crack on the block), checked it over, reassembled.
Then did the same with the carb, took it completely apart, cleaned everything, re greased all the o rings( none are torn), reassembled.
Put the engine back in the buggy with a new plug in it and its doing the exact same thing as before.

The engine has awesome top but its like the LSN is not working at all even if i completely close it off its STILL way rich on the bottom and floods, bogs ,smokes and dies if i don't pump the throttle within 3 seconds.
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Old 12-19-2008, 12:37 AM   #49
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From what you describe of the engine's behaviour, my guess is compression is lacking. Your original description, in the first post you made in the thread, contradicts my opinion because you say there's metal to metal pinch. I can't remember this and didn't go through the whole thread again, but would it be possible for you to try a different carb on the engine? Good luck, I hope you get this figured out. By all means, if you do, please fill us in on what you learn.
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Old 12-19-2008, 01:42 AM   #50
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Originally Posted by Jonro View Post
Well i don't know WTF is wrong with this engine.

I took the hole engine apart cleaned it(piston has been in the correct way and no crack on the block), checked it over, reassembled.
Then did the same with the carb, took it completely apart, cleaned everything, re greased all the o rings( none are torn), reassembled.
Put the engine back in the buggy with a new plug in it and its doing the exact same thing as before.

The engine has awesome top but its like the LSN is not working at all even if i completely close it off its STILL way rich on the bottom and floods, bogs ,smokes and dies if i don't pump the throttle within 3 seconds.

How new is this engine? Did you buy it brand new and you are having this issue? If it is used at all it could be the rod. In my Vspec I had a similar problem but it was at about the 2 gallon mark.My rod started going away(I didn't know it at the time) and I was having a really hard time getting my low end to be right but it still ran and was pretty good down the straight but it kept stalling out and then I started tuning the mid,still no good! After that I went to a playday and was still having the same tuning issue so I started tuning again and then I heard a pop and it locked up. The bottom of the rod where the copper bushing is was totally trashed. Not sure if this is the same issue but if your motor has been used at all then it is something to think about since you still have pinch. Hope that helps!!!!!!!!!!!!!!!
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Old 12-19-2008, 07:51 AM   #51
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Jonro, when I got mine, I was stumped also. The crack could not be seen. I had it flux tested to find the crack, but someone gave me a list of things to check, and it seems that you have checked all but one. I was told there may be a chipped HSN. Have you removed it completely, and checked it with a Loop, for any defects? You should drop a new engine in, and send your V-spec, to an engine repair shop, let them find the problem and fix it for you. Hope it turns out ok for you. I'm sorry you wasted your $300 like I did, but in the long run you will be better educated for it, and I'm sure whatever is wrong with your engine can be repaired. Good luck, Jaz

One more thing. V-specs are notorious for a slightly backwards tune. They run best when slightly Rich at the HSN and slightly Lean at the Low
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Old 12-19-2008, 09:14 PM   #52
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Originally Posted by motomanpat View Post
How new is this engine? Did you buy it brand new and you are having this issue? If it is used at all it could be the rod. In my Vspec I had a similar problem but it was at about the 2 gallon mark.My rod started going away(I didn't know it at the time) and I was having a really hard time getting my low end to be right but it still ran and was pretty good down the straight but it kept stalling out and then I started tuning the mid,still no good! After that I went to a playday and was still having the same tuning issue so I started tuning again and then I heard a pop and it locked up. The bottom of the rod where the copper bushing is was totally trashed. Not sure if this is the same issue but if your motor has been used at all then it is something to think about since you still have pinch. Hope that helps!!!!!!!!!!!!!!!
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Originally Posted by Jaz240 View Post
Jonro, when I got mine, I was stumped also. The crack could not be seen. I had it flux tested to find the crack, but someone gave me a list of things to check, and it seems that you have checked all but one. I was told there may be a chipped HSN. Have you removed it completely, and checked it with a Loop, for any defects? You should drop a new engine in, and send your V-spec, to an engine repair shop, let them find the problem and fix it for you. Hope it turns out ok for you. I'm sorry you wasted your $300 like I did, but in the long run you will be better educated for it, and I'm sure whatever is wrong with your engine can be repaired. Good luck, Jaz

One more thing. V-specs are notorious for a slightly backwards tune. They run best when slightly Rich at the HSN and slightly Lean at the Low
Cheers for the reply's.

To motomanpat: How would i know if its the rod? What can i do to check it?
And Jaz240: Well i have a MRT GRP that just needs the bearings replaced to pop back in that's run perfect for 4 or 5 gals so im not to worried but i think i will send the V spec off to massive mods here in Australia and have him look t it or just throw it in the bin or just set the HSN super lean and blow it up.
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Old 12-19-2008, 11:21 PM   #53
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To do a basic rod check take the back plate off, put the crank pin to either left or right side ,hold the flywheel & try to move the rod up & down on the crank pin. If you see the rod is sloppy on the pin its bad.By sloppy I mean if you can decern movement between the 2 or you see oil/fuel squeeze out between the 2 thats too much. Of course being a v-spec it could also be a worn crank pin. Think of it this way,at 40,000rpm the rod goes up at balistic speed,comes to a dead stop,then is jerked down about a hundred times in the time it takes you to blink. It dont take a lot of slop to cause problem in that scenario. You also said you took the motor completely apart, did the rod just fall off the crank pin by when you turned the motor on its ass or did you have to actually have to pull the rod off the crank. Off & on with no resistance is bad. I have no idea if thats your problem just awnsering your how to ?
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Old 12-19-2008, 11:27 PM   #54
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Quote:
Originally Posted by Jonro View Post
Well i don't know WTF is wrong with this engine.

I took the hole engine apart cleaned it(piston has been in the correct way and no crack on the block), checked it over, reassembled.
Then did the same with the carb, took it completely apart, cleaned everything, re greased all the o rings( none are torn), reassembled.
Put the engine back in the buggy with a new plug in it and its doing the exact same thing as before.

The engine has awesome top but its like the LSN is not working at all even if i completely close it off its STILL way rich on the bottom and floods, bogs ,smokes and dies if i don't pump the throttle within 3 seconds.
Are you sure the long side of the piston skirt is facing the exhaust?
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Old 12-20-2008, 12:30 AM   #55
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Back when i bought my 8ight kit i also bought a v-spec with one of the new 21J carbs on it.

No matter what i did i could not get the thing to run right, it had good top end but it would not idle and would cut out straight away.

Any how i became fed up and just bought a MRT GRP .21 and it has been nothing but perfect but it now needs its bearing replaced so now i have the V-spec back in my 8ight while i change the bearing in my GRP.

And here we go again:

It still has some metal on metal on pinch, definatly dosent have an air leak, bearings are good, replaced all fuel lines and put a new plug in it just to be safe and has about 1 and a half gals on it.

So the top end tunes ok and it has blistering top end but the LSN is a whole different story, the only way the engine will stay running is if i nearly completely close off the LSN and run it super lean.

A member gave me a good write up on the problem as he was having the exact same problem here's what he wrote:

"I was having the same issues as you were and thought I had an air leak. Yours is doing exactly what mine was. I couldn't get any temp and kept leaning it out. I would have smoke for part of the straight away and then it would go away. I knew it was too lean, I could hear it, but it wouldn't go over 200 degrees. I actually bought another motor thinking it was garbage because of an air leak or carb problem. Mine was too lean on top and too rich down low. That's why it bogs and you have to pump the throttle to keeep it running. Then you probably richend up the top so much now to compensate for the fuel being set so low on the bottom. You say you have the low end closed off. Go back close to the stock settings so it's just way rich and make sure the idle speed screw is set right. Mine would barely move at full throttle like this. Slowly lean out the top until it starts to make more RPM. Let the car sit at idle for 5-7 seconds and then punch it. If it stalls right away, lean out the low speed needle a bit and try again. Start checking temps and lean HSN accordingly. After you have done this, let the car sit for 5-7 seconds again and punch it. If it stalls, it's still too rich down low and lean it out 1 hour. Make small changes. I set my motor so it after 5-7 seconds it has the tiniest bit of rich hesitation, then clears out. If it starts spinning the tires as soon as you punch it, it's too lean. You may have to richen the bottom back up and lean the top. My buddy helped me with mine and it took about 2 tanks to get it right, but it runs perfect again. He took one look at my needles and knew what was wrong, the tune was upside down. I also had to move the screw opposite the low end screw, the one that moves the throttle barrel, in about half a turn. I don't know if this will work for you, but you are having the exact same issues as mine. Try it and see what happens. I was surprsed to. I thought my motor was junk, and now it runs fine and I have good smoke everywhere."

I followed that as best i could but its still wont run right so finally i decided to start playing with the midrange needle, he mentioned that he turned his MSN in half a turn, that helped with mine but still no go, so i kept turning and now i have it about 3 turns in and the engine will at least idle now, 3 TURNS IN. what the hell.

So what the hell is wrong with this engine, its driving me insane im just about ready to donate this thing to the nearest rubbish bin, any ideas?
Hi jonro

Generally a Vspec if ok is the easiest engine to tune and just runs like a swiss watch. You do however get the problem ones. Yours is a problem engine.

Personall I work on lots of engines and have sorted out most of them. Some you just use a paperweight.

IMO I think from what you described the carb is your problem. Remember a nitro engine is just metal put together. To get it to perform and run well thats where the carb comes in. You confirmed no issues with bearings etc.
Check under the carb for the black metal rubber coated washer. remove you carb and try another carb. This will immediately tell you a story.
Also importantly, Vspec are sensitive to fuel. Ensure good qaulity fuel as a starter. Ive seen many guys struggle with Vspecs only to discover that they were using bad fuel.

Hope this helps.
JB
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Old 12-20-2008, 10:49 AM   #56
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Have you ever heard someone say, "a Vspec with a Novarossi 2 needle carb is the best running motor I've ever run"? The Nova carbs will fit it and the Nova restrictors also fit the OS. Try one if you don't have another carb. Originally OS had problems with the press fit body carbs developing an airleak and I've even seen one fall apart. Guy went to the Speed carb and problem solved.

And yes, I'm not sure why but OS sent me a brand new case after contacting them on the phone. I sent the motor and recieved an email wanting the $90 for the service fee or $20 to ship it back. The motor had 3/4 gallon on it including break in so it was basically brand new so I was kind of pissed. However O.S. techs determined the metal to metal pinch was out of spec and termed my motor useless. At the bottom of the email was a break down stating $90 engine case, $110 piston sleeve set and rod, $30 service fee for reassembly. I almost crapped my shorts, $230 for the fix and I only payed $270 for it new. I had a long eventful conversation with the lady on the phone and we ended the phone call on bad terms Half a week later I got my motor back unassembled with a brand new in package engine case. No paper stating anything, just the motor, case and some bubblewrap. I would post a picture of the old case that cracked but you still wouldn't be able to see the crack.
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Old 12-20-2008, 11:37 AM   #57
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i have a os 20e carb i will sell for 15 shipped
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Old 12-20-2008, 01:04 PM   #58
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man i have never heard of someone having so many problems with os.. the have always been good to the people that i know
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Old 12-20-2008, 01:47 PM   #59
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If you read in the VSPec manual somewhere in the back or whatever it does say that the Vspec engine due to the nature is not warrantaible. It is strictly a "race engine" and even though I knew the book stated that she reminded me on the phone as soon as I stated my problem. They obviously knew they had a problem. My engine was the updated case one that cracked. They since have a new style case and now I even hear of people going to the JX case. So 4 different types of cases for the same engine spells "we are aware that the Vspec cases may crack" Other than that I love the engine and will probably continue to run them.
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Old 12-20-2008, 09:16 PM   #60
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jpalessi,
in an earlier post you listed some baseline settings for the carb. Is that for the 21j carb or any? I noticed that my v-spec hs the 21c carb on it, is there any problems with that one. My v-spec was given to me by a fellow racer that had problems with it, and after only 1/2 gallon of trying different things he gave up and told me to take it.(and i did). Have not tried it yet but plan to soon and wanted to try and get it as close as possible first. I have a few nova carbs if you think that would be an easy fix. I have always loved the way v-specs run and cant wait to run it,they are great engines, but dont take my word for it, hell just open ANY rc mag and look at what is winning races OS V-SPEC.

Thanks, DREW
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