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Discussion Starter #1
I just had my head rebuilt 400Km ago and everything's running pretty smoothly. So i called the machine shop that worked the head and asked when, and if, i should re-torque. After asking which gasket set i used (FelPro) he said Felpro headgaskets don't need to be re-torqued and that i shouldn't bother. I just wanted to ask here because you guys know this motor a hellofalot better than him. Should i re-torque? and if so, in how long? Thanks.
 

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Discussion Starter #3
58 foot-pounds... i think, if the MK2 TSRM specs are the same as my Haynes Manual at home... should be. I'll double check that after work. Assuming that i did torque the bolts correctly, is there truly no need to re-torque a felpro gasket? If it's recommended here, i'll re-torque them just as a precaution as i've put way too much money into the rebuild to leave anything to chance. Thanks.
 

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Most of us do the toruqe in the 70ftlbs range.
 

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Discussion Starter #6
Thank you both, that's a killer bit of info! Is there any problem with torquing the bolts that extra bit now that the engine is broken in? Is it better to do it with the engine hot? cold? Thanks again.
 

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Should not be a problem. Do it when the engine is cold.

I actually re-check the torque of the headbolts around the 500mile mark when I have done work with he 5M and had to replace the headgasket.
 

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I've researched and found the claim that max torque on the MKII head bolts is 75 ft lbs. I just replaced my head and decided to go with 68 ft lbs.

I went with higher than the oem spec of 58 ft lbs. mostly based on the premises found on this forum and supramania that today's composite headgaskets compared to the original oem gasket material are different and require more torque. I do agree that original gasket material is different than what one might buy today. So, that was enough reason for me to go with the higher torque. Whether today's different material (composite gasket) will fail at 58 ft. lbs, I don't know, I've not seen any data to suggest that; although it may be out there somewhere.

However, I suspect that over the years there have probably been thousands..even tens of thousands of 5MGE headgaskets replaced using 58 ft lbs. without issue. I think the extra torque won't hurt, may help, but in your case, since (1) you have already been driving the car subjecting the new headgasket to several heat cycles and (2) that it is running without problems, I would take the advice of that mechanic and not worry about it.

I'd more worry that by doing a retorque now, you run the risk of unevenly re-torqueing the head down now that it has heat cycled.

At this point, what is probably more important is the quality of the milling/cleaning of the head, block deck, and headbolt threads by the mechanic and if he/she torqued in the proper sequence, properly increasing the torque values until the final torque was reached.

Probably the most important thing you can now is keep your cooling system functioning properly preventing overheating in the future. That will definitely lead to a compromised gasket regardless of the torque used.

....However, if you decide to go ahead and re-torque higher, Yes. do it when the engine is cold..(not run for 12 hours to be safe), get a good quality Torque wrench, and don't just tighten the bolts. You need to first crack them loose by about 1/4 turn, then torque them to the higher amount...and of course follow the tightening pattern described in the TSRM and in the Hanes manual.

Rick
 

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Discussion Starter #10
Right, so a recheck would just entail cranking the wrench to the original value (58 lbs in my case) and checking that the wrench clicks without actually tightening the bolts any further..?? I do feel a little funny about messing with the bolts on an engine that is running fine but... i guess i have a decision to make. Thanks again for the info.
 

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Right, so a recheck would just entail cranking the wrench to the original value (58 lbs in my case) and checking that the wrench clicks without actually tightening the bolts any further..?? .
That is correct.
 

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in my book, to be on the safe side you should always do a recheck of the torques after break in. however, for you to change them and go higher after that is more risky. especially if you do crack them first and then retighten method. i think that's just asking for a weak spot somewhere. the bolts should be torqued to the correct amount the first time. i don't think though on a 5M that it would be a bad thing to go with the stock specs, but if it were me i would still go a little higher just for some extra cushion. if you aren't pushing it beyond it's limits then you are still using the engine for what it's designed for and the stock spec should be fine. what makes the difference is going turbo, or like on a 7M they found that the stock spec was too low and changed it to a higher value after too many BHG were being fixed at the dealers. the 5M never had as bad of a problem as the 7M so i don't think you have to worry unless the gasket you used does require a higher torque value for some reason. felpro are made to be oem replacements though, so nothing should be different.
 

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Head retorque

I thought I would put in my two bobs worth - If you are going to retorque the head bolts - I would - remember to UNDO the bolt about one quarter of a turn (to break the tension) then retorque to the value you want - in the correct sequence of course - I recently replaced the cylinder head gasket on a 3s-ge and after the first start up I let it cool down and retorqued - some of the bolts were just about finger tight !!! and after about 400 kms I retorqued again and got about three quarters of a turn on all of them - I probably should have used new bolts but the car is running fine Cheers pitscars
 
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