1984 ATC250R leaky head gasket, big problem!!

[30rack]

after only a couple adrenaline filled days in the dry river bed with brand new top ends (broken in more than correctly), the trikes went to hibernation through the fall and winter. Save for one extra cold day when the streets were nice and iced over, they decided it was time to do a little neighborhood ice drifting.

I made sure they were good and hot before running the trikes and all was well for about 20 minutes. Then the dreaded death rev snuck up on me. upon attempting to kickstart the engine, a "squeak" could be heard just before TDC. I was afraid of a broken piston or ring (wouldnt be the first time). I limped my pride and joy back home and stashed her for the remainder of the winter.

2 days ago I pulled off the head and found it was not a broken piston ring as I had originally expected but rather a head gasket which just couldnt make the seal. the piston and bore look fantastic.

Details: copper head gasket, leaking at or around the engine front, or so i suspect as that particular stud had to get replaced with a heli-coil and a bolt. (Its in a thread i made awhile back, I will post a link to it after this is started.). One issue is the bolt hole didnt tap exactly straight and is off a few degrees, which I suspect has something to do with this problem.

I experienced no problems running the trike under merciless load for hours in the hot summer sun, she performed beyond all expectations, but it seemed the 5 degree january weather wasnt as forgiving.

SO

I am looking for input on where I can score a fiber head gasket to provide more pliability and thus a better seal, or any other input on how I can solve this issue.

I spoke with a local ATV mechanic place and was directed to a company called "vesrah" but I wasnt able to find anything on their website for my trike. I also found through a google search "permatex copper gasket sealer" but I am apprehensive towards its use.

[SiiCHo]

go for the copper gasket sealer. if its the same stuff im thinking of, it gets sprayed on MLS (metal) head gaskets on cars for high performance builds. should work the same for a copper head gasket on the trike. it doesnt replace the gasket like rtv would, you spray it on each side of the gasket to add pliability to the copper or metal gasket, and to correct for any surface imperfections

http://www.amazon.com/Permatex-80697-Spray-A-Gasket-Hi-Temp-Adhesive/dp/B000HBNUDQ that is what im talking about, not sure if you were talking about the same stuff or not

[30rack]

for clarification, this is the stuff youre talking about?
http://www.powersportjunkie.com/PERMATEX-697-p/WPS-59-9194.htm?gclid=CNr48u7x87cCFQXZQgod0iwAXQ

[SiiCHo]

yup, thats the stuff. it stays tacky so it will fill any imperfections. i would also drill and helicoil that stud you were talking about, or just get a new jug if you can find one

[30rack]

The stud has already been drilled and helicoiled, I dont think doing it again would benefit. ill likely use a copper washer up top. Like I said, I had no problems beating the hell out of the machine through summer, It was winter time that screwed with me. I can imagine the extra-cold air coming in caused some problems.

a new jug will likely be a 300cc and thats going to carry a hefty price tag

[SiiCHo]

oh ok, the way i read the original post, it sounded like the stud was still messed up.

[30rack]

no problem.

I suspect the helicoil might have been a catalyst to the leak in that it allowed the bolt to loosen, while I dont recall exactly my dad mentioned the bolt looked loose as I was removing it compared to the other 5.

the plan now is to JB weld a stud into the block which has been bent to finish straight and go back to the standard lug up top. Might you (or anybody else) have input on something like this? I have obvious reluctance to JB welding in a stud, but if it works I guess it works.

[SiiCHo]

i would stick with the helicoil and just throw some locktite on it if it were me... i'd use the jb weld as a last resort... also, just for clarification, the helicoil was put into the jug, right? then you were using a bolt, rather than a stud? im sure if you go to a hardware or autoparts store, you should be able to find a new stud. tocktite the new stud into the helicoil (jug), and it should be good as new

[barnett468]

Hello 30rack



SURFACE HEAD/CYLINDER - I suggest you see if your head is flat. You can simply put a full size sheet of 600 wet/dry sandpaper on a granite counter top, clean the head, then color the sealing surface with a felt pen, then using moderate pressure, rotate it 3 full turns then inspect. If the felt mark is 100% gone it is good, if it is not then sand until it is. You can remove the cylinder studs and do the same thing.


SPRAY ON COPPER SEALER – I would not use it for this app IF you fix it properly otherwise it might help.


JB WELD – I’m guessing you are using it simply to keep the “bent” stud from turning. If this is the case I would use red loctite instead as siCHo suggested.


HELI COIL/TIME SERT – You can helicoil or timesert the head with a 10mm insert then use the stepped stud below. You should have a machine shop do it since you get one last shot at it. A timesert is FAR superior and will never fail.


S8X10X46 STEP STUD

https://www.belmetric.com/s8x10x46-metric-step-stud-p-1443.html?zenid=5scimedeb2e24t05pn68839eh1&cPath=9_73


HEAD GASKET – Replace with OEM only. P/N 12254-964-810

http://www.ebay.com/itm/HONDA-ATC250R-1983-84-Oem-Head-gasket-12254-964-810-/170997874372


VESRAH GASKETS – They don’t sell head gaskets for this model. See gasket set below.

http://www.ebay.com/itm/New-Honda-ATV-Parts-ATC250R-Complete-Gasket-Set-1981-1984-Vesrah-182-Antique-/151026889554?nma=true&si=g%252B%252FwMoStN%252F53YYPBTDbiTu%252BNrFs%253 D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557