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Engine head

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My guess is that you get the engine warm and maybe it'll get e z to unscrew. and i dont think your gonna need anything else exept maybe some lock tight for the srews.
 
Just get a good quality 2.5mm allen wrench, like a dynamite or trinity driver, and pop the screws loose. Then take off the old head (make sure to use the 2.5MM wrench and press down on the silver area in the head where the glow plug is, as you lift up on the purple head) and install the new one.

Re-tighten the screws in a cross pattern, like you would a 1:1 tire's lug nuts. Tighten each screw a little each time (about 1/8th of a turn) to ensure an even tightening. Get the screws as tight as you can by hand strength; no cheater bar here, and you should be fine. You will not need any additional gaskets or sealants.

The engine doesn't have to be warm, and in fact, should be room temperature.
 
Yes, it is normal for the header screws to be difficult to unscrew. And HeartBreak has given you a good deal of advice. The one additional item I would include, would be to really clean the engine, header and area around you when doing this work. The last thing you want to do is get dirt or some other foreign debris stuck in the engine after going through the trouble to remove and replace the engine header.
 
:banana: :celb2: :dance: NICE, thanks alot everybody !!! Gonna follow thoses steps carefully :thankyou: :thankyou: :thankyou:
 
Nice Dented Head...

Hi me again !! i got my header in and just to find out that it is dented (red arrow) Is there a way to straithen it or its a lost cause?
:confused: Plus, is it normal that there is that much space between the header and the crankcase, and i can see space too between the crankcase and the underhead...what do i do
AND i can put some threadlock on the screws too right?:madface:
click on it to get it BIGGERView attachment 5368
 
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I wouldn't worry about the ding. You'll get more soon enough and they really do not impact the cooling characteristics when they are that small. If several of the fins were gone or smooshed together, you might have something to worry about.

As for the space you are looking at between header and casing, it is difficult to say if that is normal or not. If you get good compression and no air or fuel coming from that area, then I suspect you are good to go. BUT I will let someone familiar with your engine and header confirm it.
 
You actually don't want to put threadlock on the head bolts of the engine; I've never done it and never had one come loose.

As long as your cooling head is making pretty good contact with the parts its' on (the cooling head is down over the silver "button"), then you should be good to go. If there seems like there is a gap between them, then I would not use the engine until you replaced it with a properly fitting head.

To check, you can remove the head and the silver button from the engine (be careful not to damage any shims, and note which direction the silver disc came off in; a sharpie mark is your friend here).

Just make sure the silver disc fits up into the cooling head, and you should be fine.
 
I wouldn't worry about the ding. You'll get more soon enough and they really do not impact the cooling characteristics when they are that small. If several of the fins were gone or smooshed together, you might have something to worry about.

As for the space you are looking at between header and casing, it is difficult to say if that is normal or not. If you get good compression and no air or fuel coming from that area, then I suspect you are good to go. BUT I will let someone familiar with your engine and header confirm it.

Thanks Skymaxx, if somebody that has that header with the 4.1 engine...please let me know if its normal or not. can't wait to go jump something !!! Thanks

Does the head has to completly cover the silver ring??
Plus it says that it fits on the 4.1 in the spec. of the chubby head.
 
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This sucks !!! the new head has about 1 mm deep and my old one, at least 2 mmView attachment 5369
Why in the hell do they say that it fits on the 4.1, but it doesn't...HELP guys what should i do, send it back or try it and see ? cuz my old head does cover completly the silver ring and touch the crankcase...THIS SUCKS !!!
 
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Have you checked the fit with the "glow button" (silver disc that the glow plug screws into) off of the engine? If you decide to pull it from the motor, be careful not to lose/damage the shims and/or get dirt into the engine.
 
Have you checked the fit with the "glow button" (silver disc that the glow plug screws into) off of the engine? If you decide to pull it from the motor, be careful not to lose/damage the shims and/or get dirt into the engine.

Yes i did ! about 20 times now, but the thing I'm worried about is, it seems to have a little space between the silver button and the crank case. I tried it and tighten the screws tight, but still a tiny space the damn silver button and the case...do i have to tight more???
 
I'd say if you have a small gap, like a half-millimeter or less, I wouldn't worry about it. My OS VZR-II's head has so much gap, I can see the top of the sleeve. Same with the F4.1 I have in my savage.

I think you'll be fine, just set your needles back to factory before firing it up.
 
I'd say if you have a small gap, like a half-millimeter or less, I wouldn't worry about it. My OS VZR-II's head has so much gap, I can see the top of the sleeve. Same with the F4.1 I have in my savage.

I think you'll be fine, just set your needles back to factory before firing it up.

OH !!! ok then, i guess I'm not has worried as i was B4 thanks again!!!, factory setting on the high speed, the low speed, and the idle?

What kind of engine head do you have on ur savage, not stock eh?
 
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I actually have the stock head on my savage; I did try the Nova head for the S25 (which fits the F4.1), but didn't like how low it took the temps. I did, however, find that it fit my OS VZ-R II and brought that engine into the right temperature zone :D.
 
As long as it seals the cylinder, it should be fine. It looks like the head just sits a little higher. The Novas and ACNCM heads do that too. Nothing to worry about.
 
I actually have the stock head on my savage; I did try the Nova head for the S25 (which fits the F4.1), but didn't like how low it took the temps. I did, however, find that it fit my OS VZ-R II and brought that engine into the right temperature zone :D.

ok ! but factory settings is for the low, high, and the idle needles right?
 
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