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I have looked at three trucks last week to buy and they all have a dead number 5 cylinder :confused: Why number five? These are all 89-95 toyota 4x4 5-speed trucks with the 3.0 v6, Pull the plug wire and nothing, my boss says rocker arms, but would only the same one go bad on all the engines? I cant take the valve cover off on a test drive since the intake has to come off to remove it. Cant find a boroscope to look into the cylinder while someone cranks it to see if the valves are not moving or if a piston is bad. I really want the last truck I looked at but dont want to spend 3,000 on a truck that needs a 1,500 dollar engine, it just doesnt make any sense. please let the magic of the pbb toyota gurus help me out.
 

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Both times that I have done HG jobs on these engines, the gasket has let go at the #5 cylinder.

Tell your boss there are no rocker arms in this engine.
 

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That makes me feel a little better. I dont mind doing a head gasket job on a truck, I actually expect it with the toyota v6. All three trucks had no milkshake in the oil and no oil in the coolant, is that normal for a toyota v6 headgasket? I apologize but the rest of my cars and trucks are older american vehicles and they usually turn the oil into a white mess when a headgasket blows.
 

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Same reason that #6 is often dead on the 7M motors. Hot spot in the motor and that hot spot cause the most expansion and contraction of the head and its spits out the head gasket first from the under torque that Toyota specs.

Toyota was FAWKING UP BAD with Head gaskets in the late 80's. ALL their engines had problems and most are traced back to too low of torque value on the bolts they are using. In the case of the 7M people tested the head bolts and found that 72lbft of torque is more appropriate then the 56lbft that is spec.The bolts were still streaching and loosing torque. I have turned head bolts at 56lbft on 7M with only about 50k on the motor.
 

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Grim Reaper said:
Same reason that #6 is often dead on the 7M motors. Hot spot in the motor and that hot spot cause the most expansion and contraction of the head and its spits out the head gasket first from the under torque that Toyota specs.

Toyota was FAWKING UP BAD with Head gaskets in the late 80's. ALL their engines had problems and most are traced back to too low of torque value on the bolts they are using. In the case of the 7M people tested the head bolts and found that 72lbft of torque is more appropriate then the 56lbft that is spec.The bolts were still streaching and loosing torque. I have turned head bolts at 56lbft on 7M with only about 50k on the motor.
Ya lost me on that one :confused: what does "TURNED" refer too?
stripped?
RE-torqued?
 

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SeaBass44 said:
Ya lost me on that one :confused: what does "TURNED" refer too?
stripped?
RE-torqued?
Lost enough torque that the bolts no longer had the correct torque.

I know you know this but for others:

Usually once a motor has some miles on it to turn a head bolt you would have to put a higher torque on the bolts then they were originally torqued to to get them to break free and turn.

I was able to get 1/8 turn before the wrench clicked to signify they were at 56lbft. I should have had to be up around 65lbft of torque to break those bolts free and start them turning. All the bolts on the exhaust side of the head (the hot side) were loosening up. I made my first pass at 56lbft and found the bolts around 5 and 6 turning.
2nd pass was at 60lbft and I was turning all the exhaust side bolts. None of the Intake side (runs colder so not as much expansion) started turning till I was at 65lbft.

It is known the 7M motor runs hot on that back corner. I bet if there was a pole on the 22R motors you would find that most blown head gaskets are on 4 or between 3 and 4. Same reason...back of the head has the poorest water circulation and runs the hottest. Bet you could prove it with a IR heat gun.
 

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Ok, that makes perfect sence now:)
I'm sure a heat gun would show like you stated.
so torque them 29% higher then TOYOTA SAYS. Hard to belive( I DO BELIVE ) that toyota was off 29%, but seems they are:eek:
 

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SeaBass44 said:
Ok, that makes perfect sence now:)
I'm sure a heat gun would show like you stated.
so torque them 29% higher then TOYOTA SAYS. Hard to belive( I DO BELIVE ) that toyota was off 29%, but seems they are:eek:

The Go fast Supra crowd were having a LOT of HG problems. A Stock 7M GTE was loosing head gaskets as early as 80K (stock there were only pushing about 5-8psi). The N/A motors were regularly loosing them around 120k.

So there was a lot of folks trying to figure out what the hell was going wrong. Unlike the V6 having a known recall, there was silent recall on the 7M. Toyota was fixing a LOT of BHG on that motor under warranty.

Somebody finally tested the factory head bolts and found that yield value was 72lb feet and everybody immediately Retourqued to that and made a significant drop on the failure frequency. After that was found everybody that was building big power motors went to Metal head gaskets and ARP head bolts.

If you want to read a bunch check this out. I read one REALLY good article that I wish I had a link to. Very informative. You would have enjoyed the read. I'm sure its in here somewhere.

http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2003-43,GGLD:en&q=BHG+Supra
 

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the toy v6 was never an official recall, rather they called it a campaign, & fixed alto of them. I don't think every owner got a message in the mail, some did, some did not.

thx for the 7m info, I knew that too had Hg problems, someday I'll get one, & first mod will be a re torque
 

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The motors probably juts need a valve adjustment, not a HG. I would start with a compression test. I see 3.0's all the time with no compression on 1 of the cylinders and all they need is a valve adjustment.
 

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if you get one throwing an o2 code when under load (pulling a grade) try leakdown test on the motor. ive had two come through my shop that had burnt exhaust valves. (both on rear cylinder drivers side) engines ran fine and idle quality was good. wouldnt throw the lite around town even when running it hard. try and take it to the mountains and bang. check engine lite. chased that one for awhile. been 3 years since the first one and it still stays off. (good friends parents 4runner) ive never been a fan of toys 3.0 motor...


chris :cool2:
 

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i heard it has something to do with the design of the exhaust creating a hot spot. headers are supposed to fix the problem.
 

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to find out if the motor you are looking at has had the head gasket recall done, get the vin and call any toyota dealer, if it has not been done, in some cases if the damage is extensive enough, they will short block the motor for you.



panty dropper said:
That makes me feel a little better. I dont mind doing a head gasket job on a truck, I actually expect it with the toyota v6. All three trucks had no milkshake in the oil and no oil in the coolant, is that normal for a toyota v6 headgasket? I apologize but the rest of my cars and trucks are older american vehicles and they usually turn the oil into a white mess when a headgasket blows.
 

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Discussion Starter #15
So if I buy this truck I can still have toyota fix it under warranty? For the recall that is.
thanks for the help guys
 

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panty dropper said:
So if I buy this truck I can still have toyota fix it under warranty? For the recall that is.
thanks for the help guys
No, that ended a few years back, though some have squeezed by 2 years after the voluntary campaign, NOT A RECALL :eek:
 

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Good to finally see someone with legitimate info on the old 7M motors! As a member of the go-fast-supra-crowd, I played that game with mine. Once the HG issue is sorted out, that is a hard motor to break!

For what it's worth, I work at a Toyota dealeship as a tech, heres my $.02:

I'd start with the basic stuff on the misfire on #5 before pulling the heads. 3.0's seem to run the best with denso or NGK plugs, and on factory toyota wires/cap/rotor. You might start by checking to see if some tard put a set of autolite or champion crap plugs in there, and if they also installed vatozones finest set of wires, cap, and rotor. I pull aftermarket junk like this off of old trucks weekly and bring them back to life by installing factory parts. Also, while Toyota did have lots of trouble with the 3.0 HG's the early engines 89-mid92 or so still had old school gaskets that seemed to seal better. I usually see burnt exhust valves, not blown headgaskets on the early ones.

In short, just start simple before you go pulling heads.

Ryan
 

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Speaking of injectors when are they coming out with a propane injection system instead of the old zenith top fogger setup?
It's funny how no one can produce a modern motor that runs using propane injection kinda makes you think they want us keep us reliant on gasoline.

Back to the subject 3.0's also have a tendancy to burn valves as well because of incorrectly shimmed valves. I know mine did after pulling the head for the 3rd time and rebuilding the motor I got it right.
I'll never drop a dime into a 3.0 motor again though. It's just a loosing battle to gain any kind of HP out it.
 

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The govt. took all that away from us. They want epa certs on everything. Even older gross polluters that WILL run cleaner on 'pane no questions. 100% politics :mad3:
Anyone with a 88 or 89 cali emissions truck that wants to help the cause,,call me! Thats what they want me to do my before and after testing on. They want that plus a lot of paperwork and lots of $$$. This is what they want for each individual engine family. So I'd have to get a 3.0 a 350 etc..
Most other states allow it and some still encourage it. Cali is crazy!
Think about it. They don't want us running around on 'pane. It would hurt the gas sales and the auto manufacturers are very closely tied with the oil industry. They cried to the govt. and they are the olly ones allowed to do street legal late model conversions. Then they partnered up with some of the crappiest lp equipment manufacturers(known problems), said they were having too many problems and shut the programs down. What a coincidence :mad3:
Older trucks should be allowed no questions asked if it passes a smog test. Shit, even make us beat it by 25% :grinpimp:
 
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