that problem sounds very strange maybe the alloy is porous or something causing fliud to leak is the carby pushed all the way down and is it tight ? another thing to check is the main needle maybe it loose and not tighten enough on the washers could be something really quiet simple i wouldnt think it be a hair line crack or porous material in the block ,, but certainly not un heard of check for simmple things first matev

Ya its very weird. I dont think its the carb though because the liquid is coming from the back of the engine. I will send you some pics.

Here are pics of it guys.

Is it just me or on the next to last pic is there a shiny line that runs where the block transitions to the mount that looks like a crack?

it does look like a crack in the block ...

When I look at it closely I can see no crack there. Would a crack affect performance because it seems to run well.

check your head bolts arnat a loose i would certainly contact your local dealer even email grp them selves along with trhe pictures but until you are sure what is going on i would stop break in for sure

ya ok. I will email grp and take it to my lhs and see what they say.

i now have 3 of these engines, bloody good engines i have replaced all the bearings in the engine with ceramics from the word go dont let this problem be your decision to go away from grp once it is soughted and you have it in your car you will be nothing but happy with the performance of it and the awsome power band nice smooth engine to drive and nice and fast i run them in my buggy and truggy

I wont, I'm not even sure its the engine yet so keep your fingers crossed.

good to hear grp awsome

any of you guys using the GRP 4 and 5 plugs? Which is better?

Hey guys I think I found my problem. I took out the engine and cleaned it and saw no cracks even with a magnifying glass and then I took the pipe off. The little rubber piece in between the manifold and the engine had a slit 3 quarters of the way around it which I think made the pipe not sit right on the engine letting the oil/nitro leak out. The bubbling I think was caused by vibration or heat. I am going to run it again soon and I will lyk.

Does this reason makes sense??

It could be. The exhaust could be blowing it toward the front of the engine and it is pooling up there.