Flushing out a 460 with it not running, any harm in that?

[VanDeano]

Would I be doing any harm flushing out my 460 with out the engine running? I was figuring since there is no water pump, it would be possible.
Reason why I ask is that sometimes I take my boat out in the salt water and the time I get home it is pretty late. I dont think my neighbors would appreciate it very much me firing my boat up. So since I just need to flush it, I was wondering would I be doing any harm by running water through it with it not ruuning.

[gotdamp]

I think the only thing you my have to watch is excessive water pressure. I have a garden hose fitting in my intake line inside the boat and flush sand and debris that way. I was initially concerned that I could damage a gasket internal in the engine with the water pressure but have not had a problem. I added a shut off valve just inside the boat and can divert water to the pump and block (for running out of the water) or just the block (for flushing).

[VanDeano]

I too have that sme set up. Im glad to hear u have not had any problems. I done it a few times, but was never sure I wasn't doing any damage.
[ August 07, 2002, 06:46 AM: Message edited by: VanDeano ]

[flat broke]

As stated the only thing you need to keep an eye on is the water pressure inside the block. So long as water can leave the block/exhaust as fast as you pump it in, you shouldn't have a problem. !!!!NOTE!!!! If you have water injected headers you need to be extremely carefull. If you turn the hose on all the way, you will almost assuredly overcome the spring pressure in the T valve and pump water up into the headers, then into the cylinders. When flushing, keep the hose pressure low, regardless of whether or not you run the motor.
Chris

[diggler]

flat broke:
As stated the only thing you need to keep an eye on is the water pressure inside the block.
ChrisWhat is the proper water pressure in a block? I hear it is around 15psi at all times except idle. (I just ordered a T-valve from Bassett). Thanks, this will clear up one of the larger mysteries I have!

[VanDeano]

Flat Broke,
I have the log type exhaust. That should ok, u think?

[flat broke]

In response to the coolling pressures in the block, safe would vary from motor to motor based upon Head gasket/intake gasket condition etc. I would say that 15lbs would be safe, but I don't know what's going on inside your motor
Van Deano,
Even though you have logs, you can still pump water into your motor if you overpressurize the block. The average garden hose puts out around 40psi when opened up all the way. That could equal more pressure in the block/heads depending on what sizes hoses you run in your system. Bottom line, keep an eye on the pressure and you should be fine.
Chris