what are some of the signs of a cracked head cause i have no overheating,just that i have lack of power but Everything else is normal.Would a cracked head give a loss of power?
possible cracked head
- Thread starter supraman508
- Start date
Yes it would. Do a compression and leak down test. What makes you think it's cracked?
Several things could cause loss of power.
Codes?
Might want to check valve timing to make sure the belt has not jumped a tooth.
Several things could cause loss of power.
Codes?
Might want to check valve timing to make sure the belt has not jumped a tooth.
i did a head job in january do to overheating and the engine sounds the same as it did before i did the head job.it has this sound that i can't explain, but if you herd it you would know that it's coming from the head.the head job went perfectly by the way.jdub;1294754 said:
buuuuut i do get the waterfall when i first start her up and whenever i step on the gas i hear water running behind the dash.i don't understand why i would hear that do to i had no problem with installing the new headgasket.supraman508;1294763 said:
A cracked head will produce symptoms like a BHG. The difference is exhaust gas gets into the coolant channels through the crack vs the gap/breach in the HG.
You can confirm with a NAPA block tester.
Might want to post up the details on the "head job"...hardware, type HG, machine work, etc. Plus any other symptoms. Playing guessing games is not my favorite thing to do.
One more (and last) time...any ECU codes?
The 7M head is kinda noisy...did you check valve and cam journal clearances as part of your work?
You can confirm with a NAPA block tester.
Might want to post up the details on the "head job"...hardware, type HG, machine work, etc. Plus any other symptoms. Playing guessing games is not my favorite thing to do.
One more (and last) time...any ECU codes?
The 7M head is kinda noisy...did you check valve and cam journal clearances as part of your work?
what i can tell you is that the head was milled by napa,the headgasket is graphite gasket,waterfall like symptoms when reving the engine,no overheating symptoms.the only code i had was a code 11.Something dealing with a "momentarly interruption in power supply to e.c.u.that was my only code,but that has nothing to do with the lack of power.jdub;1294773 said:
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jdub;1294790 said:
i DID NOT know that,but it seem more less then electrical,but then again i'm guessing
I just checked my codes and the only code that shows up is a code 12.RPM SIGNAL.no "Ne" or "g" signal to ECU within 2 seconds after engine has been crankd.Could that code restric power?supraman508;1294803 said:
supraman508;1295400 said:
Almost any code relating to the engine could restrict power...
Sounds like your engine doesn't know exactly where it is. That would be a problem.
Check your dizzy connection.
supraman508;1294768 said:
I get the "waterfall" and "water running behind the dash" sounds in my supra as well. Can anybody tell me what does that exactly mean???
87silverbullitt;1297149 said:
Air in the cooling system.
It either just needs to be burped or it indicates a larger problem.
87silverbullitt;1297886 said:
Air in the cooling system can leave you stranded on side of the road with the radiator cap blown off and lost somewhere on the highway, coolant all over your windshield, and you standing there with the 'WT' look on your face.
Aside from that, air in the cooling system means un-even cooling and/or "Hot Spots" throughout the coolant path. These hot spots could cause raised EGR/Exhaust Temps, raised temps in the block, and so on...
Plus it's pretty annoying in the winter time to all of a sudden have no heat!
Oh! Do NOT cut off the little "jiggler valve". It's there for a reason.
Plus, if you're in it that far. Just put in a new thermostat.
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Kenny - Cutting off the jiggle valve will allow a small flow through the radiator at all times. It does two things: 1) Allows the system to rid itself of air more quickly. 2) Insures there is no pressure build-up behind the thermostat that can hold it closed.
I cut the jiggle valve off every thermostat I install.
I cut the jiggle valve off every thermostat I install.
It’s been a while since I’ve visited this subject; but, the thermostat prevents coolant flow to the radiator allowing the engine to reach operating temp as quickly as possible reducing engine wear, crud deposits throughout the coolant path, emissions and such… So with the ‘Jiggler’ thingy cut out it would in fact allow air to pass easier; but, would also reduce the warm up time of the engine (and the benefits listed above) because of the now flowing coolant.
The reduced warm up time is negligible I’m sure so I think that the benefit of allowing air to escape easier/quicker out weighs the negative affects of cutting out the ‘Jiggler’ thingy.
Sorry for the mini-novel. I was just sort of thinking out loud there...
In short, Everyone Cut off your Jigglers!
The reduced warm up time is negligible I’m sure so I think that the benefit of allowing air to escape easier/quicker out weighs the negative affects of cutting out the ‘Jiggler’ thingy.
Sorry for the mini-novel. I was just sort of thinking out loud there...
In short, Everyone Cut off your Jigglers!
Anywayzz i found a retired mech that used to work at a toyota dealership back in the day when when 7m's were DISLIKED MORE by cops :biglaugh: but he told me that he would have christine running like new.so i'm gonsa just give it to him and say HAVE FUNCajunKenny;1298282 said:It’s been a while since I’ve visited this subject; but, the thermostat prevents coolant flow to the radiator allowing the engine to reach operating temp as quickly as possible reducing engine wear, crud deposits throughout the coolant path, emissions and such… So with the ‘Jiggler’ thingy cut out it would in fact allow air to pass easier; but, would also reduce the warm up time of the engine (and the benefits listed above) because of the now flowing coolant.
The reduced warm up time is negligible I’m sure so I think that the benefit of allowing air to escape easier/quicker out weighs the negative affects of cutting out the ‘Jiggler’ thingy.
Sorry for the mini-novel. I was just sort of thinking out loud there...
In short, Everyone Cut off your Jigglers!