Back Flushing?

[Foghat73]

I have a little ways before I get to the cranking point but I wondering....is it necessary to run my engine to back flush my '76 MGB's cooling system?

 

[Steve_S]

I you're back flushing the system, then don't run the engine. The water pump will be fighting the flow of water.

 

[Foghat73]

I thought the thermostat had to be open to get flow back to the radiator during the procedure to get the whole system clean?....just a question not an argument, since I obviously hadn't done this before

 

[DrEntropy]

Yes, remove the t'stat. The process can be messy, so is best done outdoors over DIRT, too... Lots of iron oxide will come out the top if you do it right.

Here in Florida the natives think sand is "dirt". I always got a kick outta that.

 

[Foghat73]

Yes, remove the t'stat. The process can be messy, so is best done outdoors over DIRT, too... Lots of iron oxide will come out the top if you do it right.

Here in Florida the natives think sand is "dirt". I always got a kick outta that.

Thanks Doc, I was thinking somewhere along those lines...


Dirt?? funny where I'm at tourists think the "sand" looks like snow. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

 

[DrEntropy]

They ain't natives.

...and they need sun glasses. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

 

[tdskip]

So if the engine is out of the car can I still back flush it, or will I need to pull the T-stat to do it effectively?

 

[DrEntropy]

t'stat needs to be out and block off the other waterpump, temp sensor and heater ports. Push the flow from bottom-up. Then for fun, push it from top, down. Should get "clear" water both directions.

 

[V6MGB]

Remove the thermostat for two reasons;
One it stops it being filled up with rubbish and ,
Two it helps the water flow through the engine more easily.

Back flushing the radiator is easily done.
Shake the unit and gently tap it to make sure any scale and rubbish comes away from the internals.
Keep going until the water flows clean.

By the way since you are doing all this you may want to have the oil cooler cleaned as well.
They can also gum up inside and flow less well than they should.

Cheers , Pete.

 

[LarryK]

Doing a back flush Dr. Entropy is right. You are restarting an engine that has been idle for a while, a new thermostat will not hurt a thing.

 

[Foghat73]

You guys are great,thanks a bunch, going to drop the gas tank this weekend and get it cleaned and was thinking ahead a bit. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

 

[Stewart]

Make sure to get it lined once you go through the trouble of having it cleaned out.

 

[Billm]

And you can just boil the tank out on your BBQ grill (filled with water of course!!). Do a search and see that several guys have done this with good results. I am planning to boil my MGA's tank next summer (that is the day here in Seattle that it doesn't rain)
Bill

 

[Steve_S]

It only cost me $25 to have a fuel tank professionally cleaned with chemicals recently.

 

[vping]

Jeese! I spent $175 to have it boiled, etched and sealed!

 

[tdskip]

It only cost me $25 to have a fuel tank professionally cleaned with chemicals recently.

That is a pretty darn good price Steve. Is there a shop name you can pass along? (Certainly OK not to if it was a favor etc...)

 

[Steve_S]

By recently I mean a couple years ago and I can't remember the name of the shop. I'll try to find it though.

Vince, sealing was probably the major portion of the cost with your tank.

 

[vping]

I assumed that too and this was just last year so prices have gone up since you've had it done. I'll see if me reciept is itemized.

 

[Foghat73]

I'll take mine somewhere to have it prepped, cleaning on the BQ grill thing sounds fun but every time I'm around a big tub of boiling water, it just makes me want to drink beer, throw some potatoes, corn and a sack of mud bugs in it..new tank on VB's site goes for $200.00+/- if cleaning cost is to crazy.

 

[DrEntropy]

Better to clean yours and know you have a GOOD OEM tank back there, foghat73. Even if it's a bit more than the replacement.

For all: IknowIknow... they say they've "fixed" the leaky batch of tanks problem, but I'd STILL keep my OLD one!