Os Cvx

[Nat'sRC]

I have a stock .12 CVX. I'm trying to get it running again after 2 years downtime. I have looked it all over and it looks good internally. It has plenty of compression. I am using Trinity racing fuel with 20% nitro. I just have a few questions before I get rollin'.
What are good base settings for idle and high speed jets?

Which glow plug is best for this? Is an A5 usable at all? I also have an MIP #8. Should I go buy an A3? It ran on the A5 and #8 before.

On a scale of 1 - 10, how fast is this enging for a small block?

 

[NCNitro]

How was the engine stored? was after run oil used when you put it up? If not it may be a lost cause. You might need to disassemble and clean the carb, you might also need to replace the o-rings in the carb. You might want to pull the engine apart and check for rust too. Nitro fuel attracts water, and water causes rust, so if any fuel had been left in the engine that long it may be a good bit of work to get it up and running.

As far as settings start with the factory settings and go from there, no two engines will use the same settings. The carb settings will depend on several things, altitude, humidity, temperature.

As far as speed, what vehicle is this engine in, the weight of the vehicle and gearing will affect speed as well.

On the glow plug I am still experimenting with those, so far I really like the OS A3, it works well in most conditions.

Hope this helps

 

[x_789]

I agree with NC on that spend 6 bucks up front get new seals for the engine and carb tear it all down again clean it well then oil it all before trying to start it. 1 to 1.5mm on the idel opening and 2 turns out on both neddles or 2 on hs and flush with barrel on the low end. Also here is the OS instructions for that engine....http://www.osengines.com/manuals/12cv-cv-x-manual.pdf X

 

[NCNitro]

I e-mailed OS a while back to get the factory settings since there was a discrepancy in their own on-line documentation, what I was told was two turns out from seated on the hsn, and 1/2 turn in from flush on the low. My truck ran like crap at those settings but it was a starting point.

 

[Nat'sRC]

I was always good with the after run oil so rust is not an issue. I took the back plate and HS off and all looked well. I cleaned that all out, but it seemed like I was just washing after run oil out. Everything was shiny and new looking. I primed with a couple drops of fuel and it started ok. I just think my settings are way off.

I know that speed has to do with weight, gearing, driver, etc. FYI it is an RC10GT full bearing kit. I have heard that hp is not the whole story for engines so that is why I tossed out the 1 - 10 stuff. Basically, I'm wondering if long term, I would be better dumping money into a new slide carb, rear exhaust motor. Really, since it is just for racing around the neighborhood, I can't see the $200 investment.

 

[NCNitro]

If your not racing it, and you can start, run and tune the engine you have, why not wait till you roast, then replace it.

 

[x_789]

I would not get a new motor .. IF this one starts and has good compression. Again I would reseal the whole engine this is to help prevent issues from a air leak cause that will make it a pain in the ass to tune.

Once you have resealed it then I would just start with the settings we listed above and keep tuning on it. Its always better to get them tuning skills resharpened on a used motor then to roach a new mill in the processs. Also for messing aroung in the neighbotr hood unless you are dead set on having blistering speed just play around with this mill to its toast.. X

 

[Nat'sRC]

OK, I can get it running with the gas I use to prime it with, but then it dies. I tried rebuilding the carb and all looked well as far as the seals went. I just cleaned it all up, function checked it and put it back together.

The glow plug gets hot, the carb and engine have been cleaned up and checked out, the air cleaner is good, it has compression and it starts on "priming gas". Still I can not keep it running. I'm thinking that the in the tank fuel filter is gummed up. I just replaced it.

Is there anything else obvious that I'm overlooking?

 

[Akina'sMtx-2]

Have you replaced the plug?

 

[Nat'sRC]

Originally posted by Akina'sMtx-2
Have you replaced the plug?

I can, but why? It gets red hot on all coils when I put the glow ignitor on it.

 

[Akina'sMtx-2]

Blow on the plug lightly, you can tell how good is the plug. If it dims and cut out completely, then it's bad. If it don't dim at all or just a little, then it's good. This is with the ignitor on it.