MILD THUNDER

iTrader: (3)

I replaced a oildyne TRS pump with a "bravo" pump last summer. The only difference I saw was the mounting bracket and plastic reservoir on the bravo. Pump worked good, actually faster and quieter than my other old oildyne pump.

However, you mentioned leaking and spraying oil? If thats happening, something else is wrong, and not the pump.

areyouliving

Do these lines get junk built up in them?? Anybody got pumps forsale??

tcelano

Has anyone used bravo trim pumps for a Speedmaster? I have old Prestolite pumps, and one is not holding pressure. Anyone have a prestolite valve body that is any good?

picklenjim

I had the same problem recently with my TRS. I swore it was the prestolite pump valvebody and even tried the valve bodies off 2 other pumps. Finally I sent my valve body in for a rebuild (go2marine.com). After that it still would drop. I took apart the cylinders and the pistons on both were loose. There's a bolt that threads into the end of the ram shaft to hold the piston on.The piston has 7 check balls in it and when the bolt comes loose it loosens the tension on the check ball springs. If it gets loose enough the springs will actually fall out. I tightened them down and replaced all the o-rings which I bought at the local hardware store for like $2 per cylinder and now it works fine.

tcelano

I found the answer, courtesy of Galen at Speedmasters-inc.

Anyway, a Bravo pump will "work"- sort of. The bravo pumps produce only about 2800 psi up/500 psi down, whereas the old Prestolite pumps and the SSM Oildynes produce in excess of 4000 psi up/1900 psi down.

Anyway, thanks for the input. I've already been through my rams and rebuilt them. For some reason, I actually had one of the shock pistons with the check balls you discussed, and the rest were solid. I thought that I might have been having trouble with the check ball setup leaking, so I welded up the passages to make it a solid piston.

In troubleshooting yesterday, I hooked the offending drive up to my trim tab pump. I then did the same ratchet strap test I'd done before. Using a big 5000 lb ratchet strap doubled up to a trailer crossmember, I hauled on it as hard as I could, and instead of pulling the drive in, it held pressure. Furthermore, the straps rang the same note after leaving it that way for over an hour, and the drive indicator didn't even budge. So, I am fairly convinced the problem lies in the pump.

I tore it down, and cleaned everything, and tried to increase the spring preload against the check balls, but I think I did that on that drive once before, and there wasn't any more adjustment left. Long story short, ordered a "new to me" Prestolite pump this morning. I toyed with the idea of just upgrading to SSM VI Oildynes, but I like how the old prestolites sound, the big oil reservoir, and I've spent more than enough money on other issues that I'll take the $200 fix over a $1200+ upgrade.