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Old 08-21-2008, 08:55 PM   #16
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Thanks for the info on the bearings, I found a set at TNT in Plano and will pick them up Sunday. I have another question, could the tank cause the engine to come back to idle very slow. Or would it most likely be the front bearing.
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Old 08-21-2008, 09:19 PM   #17
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Where is the cheapest place to pick up a sleeve, piston and rod?
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Old 08-21-2008, 10:10 PM   #18
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no leaks after the i put on the tko bearing but dont forget i have a speed ,now i have 2 ceramic bearings the rear one is from OS came stock and has not caused me problems runs flawless i only changed my front caused the leaking bothered me ,my 808 had a puddle of oil on the mount and i had no tunning issues motor ran like a champ tune it in the morning and thats it .
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Old 08-21-2008, 10:44 PM   #19
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no leaks after the i put on the tko bearing but dont forget i have a speed ,now i have 2 ceramic bearings the rear one is from OS came stock and has not caused me problems runs flawless i only changed my front caused the leaking bothered me ,my 808 had a puddle of oil on the mount and i had no tunning issues motor ran like a champ tune it in the morning and thats it .
I thought i could do the same with mine after i fixed the major air leak that the tank had and sealed the engine, thinking that the fuel in the engine would kinda plug the leak at the bearing but to no avail. For the engine to run it has to be set incredibly lean. I hope a front bearing replacement will fix it, if it dosnt it looks like i have a shotty carb.

Its funny the engine actually runs well, has very good temps... but smoke is almost nonexistent and both needles are almost closed. I definatly know its leaking at the front bearing so i hope replacing that will help.
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Old 08-22-2008, 01:38 PM   #20
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I just replaced my front crank bearing on my VZ-B V-spec - I went with the duel shielded "Power Save Racing 7x19mm Competition Front Engine Bearing" I heard of some of the TKO's leaking after installation. I talked with a couple racers that used this bearing and after there 3rd gallon the front bearing is still holding up. I didn't replace my rear bearing as mine started to leak at just a gallon and a half (Including break in).

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Its funny the engine actually runs well, has very good temps... but smoke is almost nonexistent and both needles are almost closed. I definatly know its leaking at the front bearing so i hope replacing that will help.
What are your temps at idle? Mine, idles around 180 - 190 ... I noticed I can run this engine around 235 with a little trail of smoke and plenty of power. I can lean it out more and raise the temps another 10 to 15 deg. with out any problem. If you are sucking air and your needles are almost closed, and your engine RPM's take a while to come to at idle, I'm going to suggest you are running the motor a bit lean and when the engine loads up the idle is coming down. Also, have you moved the Mid. range slide bar? I run mine flush with the carb housing to gain a little more fuel on the low end, and it help in the sweeper.

I used the oven method and replaced my front bearing. After tear down, I removed all the seals and baked for 10 minutes on 275 after ten minutes the rear bearing fell out on its own. The front was a bit more tricky, I had to raise the oven temps to 350 for 5 minutes after being in for a total of 15 minutes, I used a wooden dowel and pushed the front bearing out form the rear of the block. Going back together, I did the same in reverse, baked for 10 minutes at 350 I placed the front bearing on a wooden block, took the engine from the oven and pressed it over the bearing, it will pop in a sit flush with the engine housing, (Note: the front and rear bearing seats have a rubber seal... it's not designed to come out) I then put the rear bearing on the crank and slipped it in the till it bottomed out. It's very important to seat it with the crank and let it cool... completely. Then add some after run oil .. Add it over the back side of the crank / fuel inlet and from the rear to get into the rear bearing. I put the oil in while the engine was warm, just remember all the oil will bake in the engine if you don't clean it out first and when you assemble, you need to re-lube during installation to prevent the bearing and crank from running dry.

Good Luck either way you choose... It's not a hard as people make it out.
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Old 08-22-2008, 02:22 PM   #21
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I was thinking of sending my vspec here. http://www.ceopowermods.com/index.ph...c59ff698866cc6

Cheaper and easier to have them do it. Plus they will inspect it for you and tell you if anything else needs to be fixed.
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Old 08-22-2008, 08:37 PM   #22
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I just replaced my front crank bearing on my VZ-B V-spec - I went with the duel shielded "Power Save Racing 7x19mm Competition Front Engine Bearing" I heard of some of the TKO's leaking after installation. I talked with a couple racers that used this bearing and after there 3rd gallon the front bearing is still holding up. I didn't replace my rear bearing as mine started to leak at just a gallon and a half (Including break in).



What are your temps at idle? Mine, idles around 180 - 190 ... I noticed I can run this engine around 235 with a little trail of smoke and plenty of power. I can lean it out more and raise the temps another 10 to 15 deg. with out any problem. If you are sucking air and your needles are almost closed, and your engine RPM's take a while to come to at idle, I'm going to suggest you are running the motor a bit lean and when the engine loads up the idle is coming down. Also, have you moved the Mid. range slide bar? I run mine flush with the carb housing to gain a little more fuel on the low end, and it help in the sweeper.

I used the oven method and replaced my front bearing. After tear down, I removed all the seals and baked for 10 minutes on 275 after ten minutes the rear bearing fell out on its own. The front was a bit more tricky, I had to raise the oven temps to 350 for 5 minutes after being in for a total of 15 minutes, I used a wooden dowel and pushed the front bearing out form the rear of the block. Going back together, I did the same in reverse, baked for 10 minutes at 350 I placed the front bearing on a wooden block, took the engine from the oven and pressed it over the bearing, it will pop in a sit flush with the engine housing, (Note: the front and rear bearing seats have a rubber seal... it's not designed to come out) I then put the rear bearing on the crank and slipped it in the till it bottomed out. It's very important to seat it with the crank and let it cool... completely. Then add some after run oil .. Add it over the back side of the crank / fuel inlet and from the rear to get into the rear bearing. I put the oil in while the engine was warm, just remember all the oil will bake in the engine if you don't clean it out first and when you assemble, you need to re-lube during installation to prevent the bearing and crank from running dry.

Good Luck either way you choose... It's not a hard as people make it out.
I actually have trouble even getting it above 200, when its at full tilt it will get upto around 220, my temp reader is accurate, ive tested it, so im not reading the wrong temps.

If i tune for max performance it runs really well has a fantastic idle and low temps BUT it blows nearly no smoke(im running the top fuel we have here in aus so maybe that has something to do with it?) and the needles are nearly closed, weird aye? Ive sealed the engine, tank and lines have no leaks the only leak is from that front bearing. It should not be running with the needles almost closed, so if i replace that front bearing and it stays the same i probably have a shotty carb.

There's a reason they don't put warranty's on V-specs because they know the bearings they use are absolute junk and they would get so many returns it wouldn't be funny, i don't know why they haven't sorted out the bearing problem after all this time? Maybe they are locked into a contract with the company that supplies their bearings.

I know one thing, this is the first and last O.S. engine ill ever buy.

Last edited by Jonro; 08-22-2008 at 09:19 PM.
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Old 08-22-2008, 08:54 PM   #23
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Quote:
Originally Posted by offr0aden View Post
I just replaced my front crank bearing on my VZ-B V-spec - I went with the duel shielded "Power Save Racing 7x19mm Competition Front Engine Bearing" I heard of some of the TKO's leaking after installation. I talked with a couple racers that used this bearing and after there 3rd gallon the front bearing is still holding up. I didn't replace my rear bearing as mine started to leak at just a gallon and a half (Including break in).



What are your temps at idle? Mine, idles around 180 - 190 ... I noticed I can run this engine around 235 with a little trail of smoke and plenty of power. I can lean it out more and raise the temps another 10 to 15 deg. with out any problem. If you are sucking air and your needles are almost closed, and your engine RPM's take a while to come to at idle, I'm going to suggest you are running the motor a bit lean and when the engine loads up the idle is coming down. Also, have you moved the Mid. range slide bar? I run mine flush with the carb housing to gain a little more fuel on the low end, and it help in the sweeper.

I used the oven method and replaced my front bearing. After tear down, I removed all the seals and baked for 10 minutes on 275 after ten minutes the rear bearing fell out on its own. The front was a bit more tricky, I had to raise the oven temps to 350 for 5 minutes after being in for a total of 15 minutes, I used a wooden dowel and pushed the front bearing out form the rear of the block. Going back together, I did the same in reverse, baked for 10 minutes at 350 I placed the front bearing on a wooden block, took the engine from the oven and pressed it over the bearing, it will pop in a sit flush with the engine housing, (Note: the front and rear bearing seats have a rubber seal... it's not designed to come out) I then put the rear bearing on the crank and slipped it in the till it bottomed out. It's very important to seat it with the crank and let it cool... completely. Then add some after run oil .. Add it over the back side of the crank / fuel inlet and from the rear to get into the rear bearing. I put the oil in while the engine was warm, just remember all the oil will bake in the engine if you don't clean it out first and when you assemble, you need to re-lube during installation to prevent the bearing and crank from running dry.

Good Luck either way you choose... It's not a hard as people make it out.
you removed the inner seal right ??

this is what my guy that does all the work on my motors told me is its normal for oil to leak in the front it has to go somewhere and even though he put on the tko bearing he said you might get a little oil coming out so maybe its a normal thing and it is a sign that youre bearing gets lubed if not it will fry naturally so maybe its something else thats giving you trouble i am not a motor expert i dont take them apart or anything like that but i know every year i have motor troubles having other motor like novarossis piccos werks ive tryed them all but this year i got this os speed cause i hear its that reliable and till now it has been that and more it idles like forever ,i am on my second plug and this plug has 2 gallons on it and its still going so my point is this is what happens when you break in a motor the right way .
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Old 08-30-2008, 11:30 PM   #24
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Ok ive decided to just run the engine, till it loses compression and be done with it and maybe rebuild it later on because i have a GRP promokit on the way, but i have some questions.

The front bearing is on its way out and it leaks, now there is play in the crank shaft a tiny bit from side to side and a but more in and out of the engine, is this because of the bearing or something more sinister? Especially the in and out play.

Also will this play cause outer clutch bell bearing failures? No matter how well i shim the bell and set the mesh my outer bearing only lasts 3 tanks at most, the bearings im using are the Amain braded ProTek rubber sealed bearings, are they just crappy bearings? Or should i try metal shielded?

Also this is all running in an 8ight which i have read, due to chissis flex, that the clutch bearings become vulnerable, the king headz EZ change extended engine mount is supposed to help the problem i have one ready to install, think it will help?

Thanks.
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Last edited by Jonro; 08-30-2008 at 11:46 PM.
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Old 09-02-2008, 10:57 PM   #25
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Originally Posted by revo61 View Post
I was thinking of sending my vspec here. http://www.ceopowermods.com/index.ph...c59ff698866cc6

Cheaper and easier to have them do it. Plus they will inspect it for you and tell you if anything else needs to be fixed.

Has anyone used these guys? I've got a new EB Mod Vspec and was thinking about having the bearings switched out just to be safe...
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Old 09-05-2008, 01:41 AM   #26
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The first cure to an air leak is replacement of the rear cover gasket or the carburetor O-ring. When you install the new parts, make sure all of the metal parts of the rear cover, crankcase, or carb are absolutely clean of trash. Apply a bit of oil to coat the surfaces, and install the parts. Use model fuel on the rubber O-ring. Petroleum products will cause the rubber O-ring to deteriorate. Make sure the parts are well-seated before you tighten the bolts or screws. If your carburetor uses a drawbar to hold it, press the carburetor onto the engine while you tighten the drawbar.

A carburetor can leak air between the carb body and the throttle barrel, but this is usually confined to engines that have seen a lot of wear. An air leak here will cause idle and acceleration problems. In some cases, the fit can become so loose that the engine will continue to draw air even when the throttle is fully-closed. The cure is a new carburetor body because it's aluminum, and the throttle barrel is steel. The aluminum carb body will wear out long before the steel barrel. The rubber cover over the throttle barrel at the throttle arm is not a seal. It's there to help keep dirt out of the carb to prevent wearing out the fit between the carb body and throttle barrel.

Some people believe that their engine is leaking air through the front bearing. This is not really possible. Almost all glow engines do not use the front bearing as a seal. Even if you see a metal shield on the front of the front bearing, this is not a seal, but a cover to keep dirt out. For years, many model engines had no shield on the front bearing at all.

Some fuel leakage from the front bearing is normal. That's how the front bearing gets lubricated. The fuel that works its way through the front bearing will be thrown away by the rotation of the drive washer while the engine's running. Some of this fuel will accumulate on the engine and may even form small 'bubbles' of fuel in areas of low airflow, such as behind the needle valve. We've seen engines do this that were returned to us because of a leaking needle valve. If the needle valve leaks, it usually won't leak fuel, but suck air. You'd need a high-pressure fuel system, like pumped engines have, to cause fuel to leak out of a badly-fitting needle valve. Most fuel found on the needle valve comes from somewhere else.
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Old 09-05-2008, 01:49 AM   #27
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Ok ive decided to just run the engine, till it loses compression and be done with it and maybe rebuild it later on because i have a GRP promokit on the way, but i have some questions.

The front bearing is on its way out and it leaks, now there is play in the crank shaft a tiny bit from side to side and a but more in and out of the engine, is this because of the bearing or something more sinister? Especially the in and out play.

Also will this play cause outer clutch bell bearing failures? No matter how well i shim the bell and set the mesh my outer bearing only lasts 3 tanks at most, the bearings im using are the Amain braded ProTek rubber sealed bearings, are they just crappy bearings? Or should i try metal shielded?

Also this is all running in an 8ight which i have read, due to chissis flex, that the clutch bearings become vulnerable, the king headz EZ change extended engine mount is supposed to help the problem i have one ready to install, think it will help?

Thanks.
Loosen the mesh even more and run Avid Revolution Bearings, Get a new clutch bell as yours maybe out of round with so many bearing failures. If your bearings rock in the bell replace it. I currently get several nights of racing with these revolution bearings. I too had bearing issues until I ran Avids and a loose mesh, but a good bell is very important too.
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Old 09-05-2008, 04:20 AM   #28
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An update - after replacing my front bearing and sealing the engine. I found that with one brass head shim, (Running 20 /10 fuel) the engine would have a tendency, to flame out after long runs. The temps never got above 220. I lowered the compression by adding a second brass head shim, that seemed to help it, but I still had the problem. So. I put a third brass head shim in, and viola, the engine will not flame out or stop running unless the fuel runs out. I even let me 13 year old drive it like he stole it and it never missed a beat. I agree with oiling when rebuilding to protect the seals. I also use High Temp RTV to seal the back plate (crank cover) and neck of the carb, as well as the pinch bolt.

The other thing I've noticed about this engine is the high side needle greatly effects the low and mid settings. If I lean the high side needle, it will also lean the low and mid range. Keep that in mind as you can lean out your low end by leaning the top. Other engines are not as sensitive as this one. Its a small price for the smooth and powerful power band. I'm talking about half ticks on the needles. Not 12 to 1 - but 12 to 12.5 on a clock.
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Old 09-05-2008, 05:59 PM   #29
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Wow monkeywrench that was a great post, very informative.

Offroaden I have found the OS carb to be second to none. It is quite sensitive, but for me it holds a tune better than anything. Out of all the motors I have liked the OS ones best. I have even swapped an OS carb onto other motors with incredible results.
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Old 09-05-2008, 08:32 PM   #30
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Wow monkeywrench that was a great post, very informative.

Offroaden I have found the OS carb to be second to none. It is quite sensitive, but for me it holds a tune better than anything. Out of all the motors I have liked the OS ones best. I have even swapped an OS carb onto other motors with incredible results.
I have to agree, after sealing the motor up and tuning, this engine is a beast. I might try swapping this carb on one of my picco 26's as that carb is handful to tune.

Running this motor after getting it tuned, I was .01 of a second off the leader / pro driver in our club. Once I get some good track control, I can see myself being on top. And this Os VZ-b Vspec will be taking me there!
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