What are your thoughts?

[Lancestewart2]

Hi guys!

I put a new piston liner, piston and Conrod into my hpi 4.6 engine today, I did 2 tanks at idle, and 2 tanks less than half throttle driving in circles, all was running great during the break in period, but during the last run it started to rain, the engine seemed to lose power at times and when the tank ran out the glow plug blew and the engine was rather hot.

The air filter was wet, I'm a right in thinking that this could have been the cause of the power loss during the 4th tank, perhaps restricting airflow and overheating the engine causing loss of power?

Thanks

 

[martinho]

Usually overheating doesn´t cause power loss. I use my savage during light rain and I also observe a small power loss. But the engine doesn´t get overheated at all, it stays quite cool.

I suppose you used the break in adjusts for the engine.

Maybe the compression changed with the new piston and this may have changed the dynamics of the nitro engine. You could try to use a second glow plug washer to decrease the compression and see whats happening.

 

[BIGDAN89]

if your filter was wet and you did not go through any water puddles then its full of fuel which means its way to rich ... anyways the perferred break in method is the heat cycle which is makeing the engine run on not factory settings but only enough to get to 230 to 240 in various rpms for a few mins shut it down at tdc then cool down completely then repeat till the pinch isnt so tight.

 

[Lancestewart2]

Thanks guys,

Thankfully there were no puddles, but it was raining and I had the body off. This is the second engine I've had to run in, all others were second hand used ones with used internals, so I think it's my lack of knowledge here which has made me concerned when the engine did something I wasn't expecting.

I'm running the engine at the recommended break in settings so its very rich and the compression is still super high, i tested it this morning when putting the freshly oiled dry air filter.

Annoyingly I won't get a chance to go out today but hopefully tomorrow and I can continue the breaking in and then the fun can begin again!!

Thanks guys

 

[Mickey]

You say the engine was rather hot, what kind of temperature are we talking? Glow plugs fail quite often during breakin. Did it pour rain or just lightly rain?

 

[Upbasher]

You say the engine was rather hot, what kind of temperature are we talking? Glow plugs fail quite often during breakin. Did it pour rain or just lightly rain?

I have broken in 2 engines and both times I used the stock glow plug throughout the whole thing without it failing. The one lasted for like two gallons on top of that afterwards.

 

[Lancestewart2]

I don't have a temp gun so was only going by touch, so in fairness it may have been ok just at the higher end!

The rain was quite hard with spray from the tires too.

Normally my plugs last ages too, but it seemed to blow when the tank had finished. I'm hoping to take my car out soon, so fingers crossed all goes ok!

 

[Mickey]

I'm sure it will be ok. If you were running it out of fuel at the end of the tank it causes it to go lean which can overheat and burn the coil of a glow plug.

 

[Lancestewart2]

Well I took it out today and had a couple of issues:

1) Even though I had the settings stock, the car would rev a bit when releasing the throttle. I think this may have been due to either ritch settings or high idle which follows onto issue 2.

2) I had an idle issue, it would only idle at fairly high revs and with the wheels off the ground, as soon as I put it down the engine would cut out. After some research and taking my engine out it turned out to be 2 broken clutch springs which meant the clutch was always engaged. This has been fixed now.

Whilst I had the engine out I checked for air leaks and there wernt any.

Next run will be Tuesday so fingers crossed its a better session!

Thanks

 

[Lancestewart2]

Well I took it out today and had a couple of issues:

1) Even though I had the settings stock, the car would rev a bit when releasing the throttle. I think this may have been due to either ritch settings or high idle which follows onto issue 2.

2) I had an idle issue, it would only idle at fairly high revs and with the wheels off the ground, as soon as I put it down the engine would cut out. After some research and taking my engine out it turned out to be 2 broken clutch springs which meant the clutch was always engaged. This has been fixed now.

Whilst I had the engine out I checked for air leaks and there wernt any.

Next run will be Tuesday so fingers crossed its a better session!

Thanks

 

[IamSavage]

i find when i have run an engine in only run her for the first few tank in short runs not for a hole tank like i run it for about 2 mins runs and every now and then check the temp of engine and i found the first few tank it run high on temp due to everything is tight.
like i said i run it till temp is at it max then shut it down and don't run it again till it cold right down, like mickey said it should be fine as they do run very hot so don't panic but one of the things if you don't have is get a temp gun