Lost Power Steering Assist

[WallaceMFG]

We were running the car today in preparation to hopefully drive it, and we've lost power steering. Before we started the car for the first time, we used a drill to prime the steering system. We were fairly sure the system was bled well and didn't have any air left in it. When we started the car the first time we made sure to keep a close eye on everything. The pump never got hot, never ran out of fluid, and everything was working great. We started the car today to tune the carb and reset the timing, and there's no assist. If you look in the reservoir, it appears to be drawing in fluid, but there's no steering or brake assist. It is a Type II pump with an external reservoir, we have a hydroboost, and the stock steering box that has been rebuilt and re-valved. Nothing has been done to the steering since we ran it last, any thoughts???

[RobNoLimit]

Not sure what kind of box, but my guess is there is A) dirt stuck in the servo valve hanging it open, or B) a rough edge caught in the servo to hang it open. Try starting the car, turn the wheel all the one side and then try to turn it a little more with the pump running. If you get lucky it will free it up. If not, I hope it came from a reputable manufacturer.

[WallaceMFG]

Not sure what kind of box, but my guess is there is A) dirt stuck in the servo valve hanging it open, or B) a rough edge caught in the servo to hang it open. Try starting the car, turn the wheel all the one side and then try to turn it a little more with the pump running. If you get lucky it will free it up. If not, I hope it came from a reputable manufacturer.

Thanks for the ideas! We ended up finding out what it was later that night. The pressure relief valve in the pump had stuck open, so the pump was pumping but it was bypassing so it wouldn't make any pressure. We cleaned it out and it started working again. There might have been junk from the Hydroboost or steering box that caused it to stick, we may need to get a filter in the steering system.

[RobNoLimit]

Two things you will learn about that set-up. Heat is the enemy, and plumbing can lead to headaches. I always use a cooler with a hydro set up, on my Silver F100 I also put an inline filter in the return - typical inline PH8A, this can help cut down the cavitation at high speed. On the plumbing, it's best not to use a "T" in the returns. Use a tank that has two returns, you can get a little hydrolic pulsing with a "T" fitting. Otherwise, it's great brakes. Glad you solved it.

[cactuss4]

Two things you will learn about that set-up. Heat is the enemy, and plumbing can lead to headaches. I always use a cooler with a hydro set up, on my Silver F100 I also put an inline filter in the return - typical inline PH8A, this can help cut down the cavitation at high speed. On the plumbing, it's best not to use a "T" in the returns. Use a tank that has two returns, you can get a little hydrolic pulsing with a "T" fitting. Otherwise, it's great brakes. Glad you solved it.

Okay sir :) I went hunting for a cooler, but do you plumb it to the hydro return or the box return? And is there a certain plumbing kit to allow you to run an oil filter for this particular use case?

Thanks a bunch
Tory

[RobNoLimit]

I would place the cooler and filter in the return from the box to the tank. Also, if you do this, step up the size of the return line to slow the fluid down a bit.

[cactuss4]

I would place the cooler and filter in the return from the box to the tank. Also, if you do this, step up the size of the return line to slow the fluid down a bit.

Thank you, can't be too cautious so ordered.

Tory