Engine troubleshooting help
 

Hello,

I am having some issues getting my engine to run well. It will start and run fine for about a min and then stop. After getting frustrated I took it to the local hobby shop to have them look at it. They feel that it needs a rebuild, and that it has lost compression. My best guess is that I ran about a gallon through it which seems early for needing a rebuild. Before I buy a new sleeve and piston or new engine, I wanted to get some other opinions. Could a rebuild be the answer to the problem I am having, or will I just rebuild it only to find out that the problem is somewhere else?

Thanks,
Brian

RE: Engine troubleshooting help
 

do u have a temp gun, check the temp, if it runs till it gets warm then it might be shot. the sleeve and piston get hot and expand and have no more pinch.

RE: Engine troubleshooting help
 

I do have a temp gun. Thanks for the tip.

RE: Engine troubleshooting help
 

after one gallon the engine should still be tight, if you broke it in correctly you could get maybe 8-10 gallons out of it, how do you know that you lost compression, or maybe you just cant tune http://www.rcuniverse.com/forum/m_5517128/tm.htm

RE: Engine troubleshooting help
 

I think I can tune fine. I believe I did break it in properly, since I went off of the manufacturers break-in process which was similar to many guides that I have seen posted on the Internet. I also agree that I should get more than 1 gallon out of it which is why I made this post.

Here is a little more background. I had the Traxxas engine for a while and eventually got rid of it because it wasn't that great. I broke that engine in fine and it lasted a few gallons before I replaced it. At the time, there were not a lot of .15's that would bolt right on to the T-Maxx, and the HPI 15ss was one of the better at the time. I purchased that and had that running great. I recall only running about a gallon through it, but it is definitely no more than 2. The 15ss always ran great, it was the truck that sucked. Eventually I got tired of always fixing it, so it sat on the shelf for a few years. I decided to give it to my brother and shipped it off to him. When he got it the weather was totally different and it needed to be re-tuned. After trying several times to tune it I gave up and took it in to the LHS. The guy there, which may be no better at tuning than me, wasn't able to do any better than I was. He felt that the compression was low. There didn't seem like a great deal of resistance to me either, but I hadn't used it in years making me a bad judge.

All the fuel lines were replaced to eliminate the possibility of having an air leak in the fuel line. The tank was new as well, so that seemed like an unlikely cause. It had new gas in it. The only other possibility in my mind is there is a leak in the carb, or it is worn and needs a rebuild.