D
What it does is prevents the impeller from cavitating which basically means spinnig and moving nothing. The plate makes it so when that impeller spins it prevents the water from escaping thus Forcing it through your system when you need it most. I posted a better picture so you can see a little better how it works, and how easy it is to make your stock pump into one. I first got one many years ago for my old 78 suburban from a company in san luis obispo called Brassworks/Flowkooler.
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If the car is low on coolant, it is going to cavitate anyway.
And yes, I am in the Anbar province. No, I am not in the military.
And yes, I am in the Anbar province. No, I am not in the military.
But when its full of collant and the system is working perfectly is it cavitating? thus causing hot spots that lead to BHGs'?
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Geezer, that's an awesome idea that I can say I've never heard before! *Goes to pull water pump off old motor*
I'd say this is unlikely.suprageezer said:
I'm going to quote the doc for a second here, and say that the weakest link in the 7M engine is the owner.
From experience with my personal engine - when I was TRYING to blow the head gasket up and couldn't do it, I was pushing 20psi with a stock CT26 on a stock headgasket torqued properly. The engine refused to die until I upgraded the CT26 to a bigger trim and left the boost controller at 20.
The weakest link in the 7m is the stock headgasket, reguardless of who owns it.
You can quote me on that :rofl:
You can quote me on that :rofl:
I have never ever seen a low mileage 7M headgasket just blow. You don't have to be low on coolant to over heat the engine either.
swaq said:
Hear the message, don't kill the messenger. :biglaugh:
I made it my sig, no quote needed. LOL
Nick M said:
It happens, even though you have not personally seen it. You don't have to overheat it to get a blown headgasket.
Look at these two pictures. You can see that the fire ring has gone egg shaped and the coolant passages crushed in. This is the classic failure mode. It is clearly related to the overall weakness of the gasket in the direction of the coolant passages.
Also note that the typical wear patterns on the block of a blown 7M show depressions of about 2 mil under the fire rings. This indicates that the fire rings are moving around probably due to the difference in expansion of iron/aluminum. As those grooves wear in, the force squeezing the fire rings is getting weaker and the movement will get worse. No amount of bolt tightening is going to save you at that point.
The MHG has two important advantages. First, the multi-layers slide on each other during the warm-up/ cool down cycles and prevents the fire ring grooves from forming, and the gasket is much stronger in the direction of the coolant passages.
By the way, my (purchased new) 90T showed signs of a BHG at 60k miles (gurgling, very slow loss of coolant, formations on plug #2). It finally blew big time at 110k miles (7 years after I knew it was going bad).
I changed the coolant every two years or so with red Toyota stuff, and this car has never overheated ever. The BHG is not related to any fundamental cooling issues. There was no coolant corrosion at all inside my engine when I disassembled it.
Also note that the typical wear patterns on the block of a blown 7M show depressions of about 2 mil under the fire rings. This indicates that the fire rings are moving around probably due to the difference in expansion of iron/aluminum. As those grooves wear in, the force squeezing the fire rings is getting weaker and the movement will get worse. No amount of bolt tightening is going to save you at that point.
The MHG has two important advantages. First, the multi-layers slide on each other during the warm-up/ cool down cycles and prevents the fire ring grooves from forming, and the gasket is much stronger in the direction of the coolant passages.
By the way, my (purchased new) 90T showed signs of a BHG at 60k miles (gurgling, very slow loss of coolant, formations on plug #2). It finally blew big time at 110k miles (7 years after I knew it was going bad).
I changed the coolant every two years or so with red Toyota stuff, and this car has never overheated ever. The BHG is not related to any fundamental cooling issues. There was no coolant corrosion at all inside my engine when I disassembled it.
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Agree with Pi.
number of bhg's/thousand toyota's = A
number of bhg's/thousand 2jz = 1.5A [high performance, owner abuse, etc]
number of bhg's/thousand 7m = 150A
There's a design flaw(or series of weakness). Toy knows it, and I'm sure they have an internal doc from 92 outlining the flaw, the fix, and the recall cost. Guarenteed.
These days they care a bit more about perceptions and just added extended warranty to the v6 with the oil system flaw that allowed sludge buildup and trashed "150A" of those engines...
number of bhg's/thousand toyota's = A
number of bhg's/thousand 2jz = 1.5A [high performance, owner abuse, etc]
number of bhg's/thousand 7m = 150A
There's a design flaw(or series of weakness). Toy knows it, and I'm sure they have an internal doc from 92 outlining the flaw, the fix, and the recall cost. Guarenteed.
These days they care a bit more about perceptions and just added extended warranty to the v6 with the oil system flaw that allowed sludge buildup and trashed "150A" of those engines...
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Turbo. Targa. Life. said:
huh? the v6 with the oil system flaw is 1997-2002 Toyota and Lexus vehicles with 3.0-liter IMZ V-6 engines and all 1997-2001 Toyota vehicles with 5SFE 2.2-liter 4-cylinder engines . Toy will cover the cost of sludge-related repairs for eight years from date of initial sale.
My point was in 92 toyota didn't give shit. In 2007 they are a bit more concerned about perception now that most of the cars/trucks they sell in america are made by americans.
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Oh, sorry, lol i mis-read. I thought you were saying the 2j's were v6's. You don't know HOW many people think that all supra's are v6's :nono:
oh and btw my comment was a sarcastic joke if you didn't catch that
oh and btw my comment was a sarcastic joke if you didn't catch that
Do you think it is coincidence that only leased vehicles had a sludge problem?
That is a rhetorical question.
That is a rhetorical question.
Yeah, even though Toyota finally settled on these so-called sludge monster engines there are hundreds of thousands of them that never had the problem. Me thinks it was more maintenance related than design. Based on what the average person knows about oil I wouldn't be at all surprised. That said anyone who buys a car shouldn't have to be a whiz on oil to avoid problems.