Thanks, does that 12mm fit onto the pump on your 5.5 aswell? And what do use for the gearbox in it?
Haven’t installed them in the pumps yet. But I need to. I am not sure on the size. I was going to order a 12mm and try it when I changed the pump oil.
I would think it could be 1/4 or 5/16 for the pump, with GP designed in USA while Honda is using metric
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Possibly
Just looked at my notes. The Allison 5.5 pump is a 3/8 and the Udor CKC 30/24 8GPM is a 3/8 as well. That’s from the makers. I can’t speaker to other pump sizes.
Drainzit Oil Changing Aid - model# STAN1438 with A 3/8" Drain Port Size https://www.amazon.com/dp/B000PDN3HY/ref=cm_sw_r_cp_api_fabt1_OM0VFbVSQZ4Z6
HOMPAT Mini Ball Valve 3/8 NPT Stainless Steel 316 Ball Valve Male to Female (3/8" Ball Valve) https://www.amazon.com/dp/B07F3VS4NJ/ref=cm_sw_r_cp_api_fabt1_FQ6VFb5JGHPC1?_encoding=UTF8&psc=1 I’ve seen guys use these before if it’s 3/8, put a barb on it and hook up some poly hose when it’s time to drain, might give it a try and put two on I case one accidentally gets opened
You need 3, what if the other 2 fail.
so the pump came in today but i noticed a rod that goes into the shaft (i hope thats what it’s called) but does not fit in the new pump
![image|281x499]
it fits perfectly on our motor but not our pump. what would be the solution for this? as ordering a new rod that fits the pump means it wouldn’t fit the motor.
Your GX390 shaft and that rod is the key way. It should fit the gearbox. Is it not going in at all or it’s too long?
Also did you use copper anti seize on it?
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i don’t have the 390, it’s a simpson 420cc motor. i haven’t used copper anti seize. the rod just falls out of the cutout as shown in the last photo
Right you went the key way sitting in the slot of your shaft. Keep it vertical to keep it in. If you have issues you can hold it on the shaft with a zip tie. Then cut the zip tie off once it’s partly inside the gear box. Then apply copper anti seize. Then slide it inside the head drive.
I’m not 100% on your shaft size but mine is
Shaft Diameter (in.) 1
Shaft Length (in.) 3 31/64
if it’s not somewhat perfectly fit in there will it cause any damage? i’m worried it might rattle around at the bottom of the gearbox since it’s pretty deep
also when i put the pump on with the rod in, the holes for the screws wouldn’t line up with the motor, just barely off to the point where i couldn’t put the screws in
It should slide into the gearbox on the pump and be snug. No rattling.
Your gearbox has the adjustable holes in the mount. Those won’t work?
