Can my cooling head be fixed

[Paul11277]

Well in an earlyer post i said my engine sounded chocked. Well today i went out and checked a few things out on my max. Restored the tuning back to factory settings and started it her up. She ran great for about 10 mins then there was a bit of a pop and she cut out. So i went to restart it and found i had no glow plug. So i attempted to fit a new glow plug to fint out the the head was stripped bear of threads.

Why would this happen and can it be fixed. I have already orderd a new one from ebay...

http://cgi.ebay.co.uk/REVO-T-Maxx-T...34063QQcmdZViewItemQQ_trksidZp1742.m153.l1262

This seemed like a bargain to me and cheaper than i could even dream of getting one in the uk. But if anyone can offer any reason as to why this would happen and what i can do to prevent it i would appreciate it becasue this engine had only just had 2 gallons of fuel through it.

 

[rckid91]

never seen that happen possibly cross threaded and ruined the thread

 

[Rolex]

My guess is that at some point it wasn't tightened properly and vibrated when the engine ran. Eventually the vibration was enough to wear down the threads in the aluminum head.
In case you're wondering, yes, they will run with a loose plug. Not great, but they'll run.

 

[Paul11277]

Well i got my new head and fitted it. Its much bigger than the stock one but looks great. However i still have the problem of my engine sounding choked after about half a tank of fuel. It just starts dropping power untill it cuts out and refuses to start again. I have adjusted the hsn back to factory settings and it still does the same. I cleaned the air filter and that made no difference. Should i strip my carb and give it a clean although its only had 2.5 gallons through it at the very most. It just dont make any sense why it would run fine for the first half of the tank. Could it be a fuel pressure problem between the exhaust and the tank. When i first got my max it had a slightly wider gauge fuel line on the exhaust to fuel tank side than it did on the fuel to carb side. But i replaced all the fuel pipe with the same stuff. But it has ran fine like this for a gallon of fuel or more. I'm beginning to think i should bin my trx25 and buy a good motor instead but would like to get this one going if anyone can help.:surrender

 

[3.3maxx]

sounds like a fuel pressure related problem to me. Uou should try running a dual tank set up. Just get a little mini me tank. it shoudl stabalize the pressures and also the temps. Have you checked your temps to see what they are at when it cuts out??

 

[Rolex]

Absolutely, check your temp. It sounds like the LSN is set too lean, and when it gets hot, it quits.

 

[Paul11277]

I shall have to look into temps because i dont have a temp gun. It may also be worth mentioning that i seem to blow a glow plug for almost every tank of fuel i used. Also since fitting the new cooling head it is much cooler than normal because the head is almost twice the size of the old one. I can tell this just by touching it. But my last plug looks like it has been hit by the piston because the coil is squashed almost. I am now waiting for a new plug to arrive so i can have another go at the weekend. But it is highly possible that the lsn is out because my truck will wheelie on demand no jerking the throttle just nail it and its up there. Any help on the blowing glow plugs so often would be a great help i have tried variouse plugs but not one of them stood out as been a better plug. My truck is quiet difficult to start aswell so i have just ordered as OS A3 to see if this sorts the difficult starting out.

 

[jon2]

It is common to have the 1/2 tank lean issue. Most will see it because the tan does not have a system that keeps the tank equally pressurized even when the tank goes lower.

You may have to re-tune because the head may give you a false condition.

Look for a good smoke trail, decent acceleration and decent top speed and a temp of about 210- 230ish. The higher limit in temps are subject to the user's preference.

 

[3.3maxx]

the 3.3's tend to run a bit hotter than 210-230. Mine likes to run around 270-290. now I know 290 is wayy to hot. but that is what she wants to run at. The problem your having with plugs is a lean issue. I suggest you re-tune the truck after the cooling head install, start out at factory settings and go from there. I have also noticed that an aftermarket pipe will also make this mill a little harder to tune. What type of pipe are you running now?? Also try running a colder plug. This will make it a little harder to start but it will also bring the temps down a little. What type of fuel are you running as well?? This will also have a major impact on running temps. You may also as mentioned above try using a dual tank. Just a little guy will be fine. This just helps stabilize the temps/pressure all the way through the tank.