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Damn Crank bolt....Any ideas please?


and1c

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ok guys.

I borrowed a compressor off a friend, I was dubious if it would do the job as its only 7CFM output but I got it setup and bought the airline and whatnot to run the CP 1/2" impact gun I bought recently.

 

Just made a concerted effort on the crank bolt and its not budged after a lot of attempts :(

 

The compressor had enough power for the impact gun I think, it was set at 7 bar and the gun had a fair bit of impact time until the motor kicked in to refill the tank.

 

In the end I gave up because even with a brand new impact socket, the bolt was starting to shine a little on the edges and I was worried about rounding it.

 

The engines on a stand so breaker bar is not a possible option.

 

Any ideas as to what to try next?

 

bigger compressor?

 

new impact gun?

 

B*gger

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i had the same problem, engine was on a stand and i spent hours tryin to undo it! in the end i just ground it off with a grinder! sounds a bit harsh i no but i got it off, new bolt was only about a fiver so not too bad

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You need a better or bigger (3/4 drive) impact gun, and about 160 PSI, although the compressor should hold enough air to undo or do it up just fine.

 

Thanks Chris.

This Cp should according to the spec 'should' have enough power to do the job. And its rated to run at 90psi max.

So either the impact gun doesnt do as it should or this compressor is not manly enough....

 

I even wound it up to 8bar pressure in frustration (not good for prolonged use on the air tool) and ...nada

 

The only thing I can think of is I only had an 8mm air line and this gun is supposed to run with a 10mm one.

 

Im going to try a new line but have a feeling it wont make zip difference to the outcome :(

 

 

Specs

 

Working Torque Range

Ft.-lbs.(Nm) 25-400(34-542)

 

Max Torque @ 90 PSI Rev.

Ft.-lbs.(Nm) 550(746)

 

Free Speed(rpm) 7,000

Weight lbs.(kg) 5.6(2.5)

Length in(mm) 7.1(180)

Avg Air Consumption CFM(l/min) 4.75(106)

 

 

Does anyone near Sheffield have a bigger compressor/and or impact gun who would be kind enough to call by with it sometime soon? :eyebrows::D

 

Owage will happily be repaid in the form of any mechanical assistance you need a hand with or a few beers :innocent:

 

Alternatively Im going to have to buy a bigger impact gun and hire a proper beast of a compressor (diesel one :D).

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Thanks Scooter. Nifty idea that one :)

 

Unforunately Im a bit pushed for space and hands at the minute and dont fancy lifting it out of the workshed to try and get it in a good position for bracing!

 

Molak. Did grinding it work ok then? you didnt nick the nose of the crank?

Sounds a bit high risk to me!!! :)

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A 10mm line will make a substancial difference.

 

ok. cheers mate.

Will try that tomorrow then.

 

Heres to hoping it does the trick!

 

edit// boll*x

 

its Bank Holiday weekend. Make that tuesday I will try it

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Guest MikeSupra

Put some engine oil (new obviously) down the air inlet pipe of the gun, this is how i got mine off as it gives the gun more power. Only for the first couple of hits though! Dont be affraid to put quite a bit of oil in, just make sure you're gripping it tight becuase its not as forgiving with oil in!

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i really dont think you have enough torque on that gun mate, i tried a cheapo gun when i took mine off and ended up borrowing off a mate who had a proffesional heavy duty 750 nm gun (expensive) and we still ended up with stillys and a bar on the impact socket as well :blink:, when you have some think tightened up like that nut the actual breaking torque to take it off is massive, btw this was all in the car, if the engines out of the car i rather like the idea of grinding the ferker off, bit extreme but it would probably take about 20 minutes as opposed to the week of messing i did borrowing gear etc

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Thanks Scooter. Nifty idea that one :)

 

Unforunately Im a bit pushed for space and hands at the minute and dont fancy lifting it out of the workshed to try and get it in a good position for bracing!

 

Molak. Did grinding it work ok then? you didnt nick the nose of the crank?

Sounds a bit high risk to me!!! :)

 

I don't blame you........it was a last resort for me.......

 

I've not taken a grinder to one, but i know that the bolt has a very large washer behind it, probably 4-5mm thick which 'should' stop you straying to near to the crank........

 

Just as a heads up i had further trouble with the next stage of dismantling as the lower cambelt pulley was very reluctant to slide off the crank/keyway........sometimes they pretty much slide off but this one didn't. Its difficult to get a normal puller behind it (at least initially) but it has 2 bolt holes so you can pull it off using x2 bolts (i used 2 long camcover bolts) and a spanner etc laid across them, and between them and the crank snout.

 

Also in case you haven't done the sumps yet, i find the lower black sump a PITA to break the seal on. With all the screws removed its still very reluctant to part company with the ali 2nd sump, and being ali i felt the need to be careful choosing what i tried to pry it away with. If you have something like dental floss or fishing line then you can saw away at a corner to open up a gap to pry into with a gasket scrapper/old wood chisel etc.

 

The second sump is a lot easier as the purpose made recesses between it an the block mean you can get a lot more leverage on it.

 

Have fun :)

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I don't blame you........it was a last resort for me.......

 

I've not taken a grinder to one, but i know that the bolt has a very large washer behind it, probably 4-5mm thick which 'should' stop you straying to near to the crank........

 

Just as a heads up i had further trouble with the next stage of dismantling as the lower cambelt pulley was very reluctant to slide off the crank/keyway........sometimes they pretty much slide off but this one didn't. Its difficult to get a normal puller behind it (at least initially) but it has 2 bolt holes so you can pull it off using x2 bolts (i used 2 long camcover bolts) and a spanner etc laid across them, and between them and the crank snout.

 

Also in case you haven't done the sumps yet, i find the lower black sump a PITA to break the seal on. With all the screws removed its still very reluctant to part company with the ali 2nd sump, and being ali i felt the need to be careful choosing what i tried to pry it away with. If you have something like dental floss or fishing line then you can saw away at a corner to open up a gap to pry into with a gasket scrapper/old wood chisel etc.

 

The second sump is a lot easier as the purpose made recesses between it an the block mean you can get a lot more leverage on it.

 

Have fun :)

 

 

Scooter.

Thanks for the info bud :)

 

After briefly looking at the grinding method someone mentioned above I have shelved the idea as I cant see how it will be successful.....

 

If the head is successfully ground off the bolt, it will leave a stump of bolt stuck in the thread.

 

Meaning that although the pulley etc will come off, the game is not over by a long shot :search:

Now I know from having to grind a few bolt heads off in the past, that a lot of tension is lost from the bolt when the head is removed...however I dont fancy finding out the bolt body is still stuck in the thread and then not be able to remove it without damaging the crank.

Apart from the fact that grinding stuff like that gets metal fragments EVERYWHERE and I dont fancy splattering them all over a half stripped engine prior to a rebuild :D

 

So, it looks like I will have to cough up and get a bigger 3/4" Impact Gun and possibly a bigger compressor. :(

 

Thanks for the heads up on the lower cambelt pulley. Point noted on that!

 

As for the lower black oil pan.....10:4 on that.....I agree totally :D It was a right PITA to get off and I was starting to get a bit annoyed with it.

 

Ended up using some piano wire and a couple of chisels at strategic places and managed to ease one side loose and remove it .

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Scooter.

Thanks for the info bud :)

 

 

no problem, i'll be interested to see how you get on with the rebuild. I have everything to make a TT short block i'm just notoriously bad at moving things on.......plus i really need to work on getting a clean area to assembly it.

 

Next stage for me is trying to find the best way of cleaning everything up, to start with i'm going to try Loctite 7200 (as recommended on here) to remove the old sump sealant.....

 

BTW in case you misplace a sump bolt, or internal nut/bolt for the oil strainer baffle etc, i have loads of spares knocking about...

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The snag with drilling or grinding the bolt head off is if someone has loctited the bolt i. The threaded portion is then loctited in the crank snout... Bigger gun. Or if you are renewing the damper just use some heat.

 

Good point Chris!

Bigger gun it is then :)

 

ps/ I am renewing the damper though

 

Scooter//

 

Cheers..I may need to take you upon that offer of a few nuts and bolts along with way :D

 

Once Ive got the damper off and checked the mains and crank Im going to get the block sent off to the engine machinist.

 

They are going to hot tank the block, then Im getting it rebored to .5mm over and then getting it honed etc

 

Block and head are getting machined to a fine surface finish and flatness. (both are in spec as is)

 

Im using standard main caps and stock fasteners (dont fancy an align bore as success rate is 1 in 3 according to several Pro shops I have asked!!)

Using ARP head studs.

 

CP forged pistons and Carillo conrods....+ some other fruity bits.

 

Using a new oil pump, Ive got a full new engine overhaul kit (new seals, gaskets etc)

 

 

Cylinder head is getting a port and a polish with oversize valves and Jun Ti valve springs.

unsure on what cams Im using at this time

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Im using standard main caps and stock fasteners (dont fancy an align bore as success rate is 1 in 3 according to several Pro shops I have asked!!)

Using ARP head studs.

 

 

 

Cylinder head is getting a port and a polish with oversize valves and Jun Ti valve springs.

 

good info on the main caps as this confirms my suspisions, i have read in several none Supra related publications about ARP studs being able to pull main caps out of true due to the force they can exert, now this isn't a bad thing as long as you are prepared to get the caps align honed which i am not for the power level i am running.

 

Out of interest what is going to be the spec of the engine to warrant over size valves, everything i have read indicates stock valve size to be more than adequate for anything other than silly laggy horsepower and having experience of head porting i would be very sceptical of "claims" made for a "ported" head, i have done a lot of research into this and have been studying a 2JZ GTE cylinder head that has now been sat on my garage bench for months, it is heavily influenced by Cosworth design (the Japanese know a good thing when they see it:D) and to be honest all i can come up with is radiusing the central inlet port web, hogging out where the injector feeds into the head (just a little), taking the valve bosses down (again just a little) and a mirror polish for the exhaust ports, the only port matching to be done would be on an aftermarket exhaust manifold as Mr T has done an outstanding job everywhere else. My point is you could spend an awefull lot of money on that head and with all probability sacrifice a lot of your low and mid range for a piddling unoticable 10 hp when bouncing off the rev limiter

Edited by paul mac (see edit history)
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..

 

Out of interest what is going to be the spec of the engine to warrant over size valves, everything i have read indicates stock valve size to be more than adequate for anything other than silly laggy horsepower and having experience of head porting i would be very sceptical of "claims" made for a "ported" head, i have done a lot of research into this and have been studying a 2JZ GTE cylinder head that has now been sat on my garage bench for months, it is heavily influenced by Cosworth design (the Japanese know a good thing when they see it:D) and to be honest all i can come up with is radiusing the central inlet port web, hogging out where the injector feeds into the head (just a little), taking the valve bosses down (again just a little) and a mirror polish for the exhaust ports, the only port matching to be done would be on an aftermarket exhaust manifold as Mr T has done an outstanding job everywhere else. My point is you could spend an awefull lot of money on that head and with all probability sacrifice a lot of your low and mid range for a piddling unoticable 10 hp when bouncing off the rev limiter

 

Interesting info Paul :)

 

The spec of the engine is intended to be 'bullet proof' (I hope) and turbo choice is still under consideration.

Suffice to say it will be larger or equal to a GT40R :eyebrows:

 

Point taken on the cylinder head work..... I will have to look into this further before chucking dosh at it.

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  • 1 month later...

Have you still got the flywheel attached to the other end of the crank with the engine still on the stand? If so what you can do is make a brace out of thin sheet metal between the flywheel and the block. It doesn't have to be very thick, just a couple of mm.

It literally just has to be a piece of metal with 2, preferably 3 holes. 1 that you can use to put a bolt through to the flywheel, and 2 to bolt to the block.

Then all you need is a breaker bar, a decent socket, a bit of elbow grease and possible 1 other person to hold the stand steady / counterbalance it.

 

I've got a picture of the brace I made somewhere. I'll try to find it out and post it up.

 

You still need to give it some though. It took all 13 stone of my dad bouncing on the end of a 3 foot breaker bar for mine to finally crack.

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