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Tips on removing cambelt sprocket from crank?


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Hey guys, just having alot of trouble removing the cam sprocket from the crank. I have the front cover bolts out, the crank is just sitting in there, bearing cradle removed. I just can't see a way of getting that sprocket off, I have tried levering the front cover off with the crank (bad I know) with no results. I can't get a puller behind the sprocket, and I can't remove the crank untill I get it off. How the hell do the rest of you guys get it off?

Any ideas appreciated.

Cheers. Nick

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Nick, I put two prybars behind the pulley and pulled it somewhat gently. Pulling evenly is the trick. Once the pulley popped loose it slid right off.

 

In the states we have a penetrating oil called Kroil or Sili-Kroil (I have this) and I can't even describe how well this stuff works. Makes life much easier. I would say its almost as good as a torch.

 

Evan

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mine was on like a beeyotch.

 

what i did was use two pry-bars aswell. it got them as close to the rear as i could, and i just thrusted forward on the handles as evenly as possible.

 

I sorta didn't do it gentle, cause it just slipped off, i had to pretend i was shoving the prybars a bit, to get it to kind of jerk the gear out of place. it's that initial force that you give it that will break loose any small rust that forms in there that would potentially seize it on just a touch. removing it relatively no force will lead you nowhere if it's seized on there.

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Hey guys, thnks for all the responses.

My main problem is that I don't have any room to get anything behind it, I'm thinkin about rigging up the engine stand to the crank and trying to pull it straight up with the front cover still attached, once off I think the pulley might be easier to man handle.

I am kind of releaved that I wasn't called a dumb F^#K and I missed an important detail somwhere, glad it's a common problem.

I think I may have to go with the drilling and tapping idea, or maybe a bit of wire I could get behind it then slide hammer it off.

Will takle it again tonight and update, better head to work.

Thanks for all your help.

Cheers. Nick

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A friend of mine has dealt with a few of these, and ended up talking to NizPro here in Australia to see how they did it. If it doesn't come off easily, then drilling/tapping/puller is the standard solution. I saw one he pulled from an RB30, and even after drill/tap/oxy it was still a pain to get loose - some people get their engines very wet, and it's a bad place for rust to form.

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well if rust seems to form on the gear, you could always slip something over the crank snout (a pipe, maybe) and give it one nice whack so that it pushes the gear back. that outta loosen the gear a bit. then take a towel and wrap it around the gear and use a pipe-wrench / channel locks to twist it up off the snout a bit, then use a pry bar.

 

I had trouble with mine too, but i used a screw driver to get enough clearance behind.

 

I actually used two screwdrivers with solid steel tips (not magnetic tips, they chip easily) and twisted them in my grip, to push away from the back of the oil pump housing.

 

it will come up SLIGHTLY.. bit by bit. barely looks like it's coming. I had the same problem with my stupid crank pulley too.

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twisting it off the snout a little bit would be a great idea if it wasn't for that damn little key way. Can anyone think of whats stopping me from pulling the crank straight up with the engine crane, with oil pump/ front cover and cam pulley still attached?

As I said before I think once off I would have more room to get somthing behind it, like a tyre iron.

Nick

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when you say straight up, do you mean pulling it with the engine upside down, or pulling it with the engine sitting on the rear main seal.

 

either way, i don't see either as being too good an idea if you intend to use the crank, unless it takes very little force. and chances are, you're going to have to grip it from a rod journal. maybe not the best idea. if you pull it with the engine on sitting on the rear seal, well... you have the main cap thrust areas that will not let the crank move more than half a millimeter anyways, so i dont know what that would achieve.

 

also. what you probably COULD do, is loosen all the bolts on the oil pump, and give it a tap from the back side, so that it pushes the crank sprocket forward a bit., then when you seat it back in the position it is when bolted in, you should have screwdriver clearance.

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DO NOT put any levers behind the gear unless you intend to replace your oil pump, even gentle pressure on the oil pump housing will distort it and cause it to fail.

 

There is a very easy way to get them off, takes me about 30 seconds.

Get a drill about 8mm (5 16ths) and drill into the gear directly above the key slot evenly between the key slot and the teeth on the outer edge.

 

Mark the drill with a pen or put some tape on it to indicate how deep to drill, drill in till you are 'just' about to drill right through it.

Then with a reasonable sized chisle, hit the outer edge of the gear, between 2 teeth, directly above the hole you have drilled, the gear will crack straight through between the teeth, through the hole and into the key slot, they then just slide right off.

A new gear is inexpensive and having stripped 100's of RB's I have found this the best way to go if they don't just slide off by hand.

 

Hope that helps,

Rob

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rob, that exactle what I needed, a PROVEN technique, I wouldn't have thought of that. I will definately do that tomorow and let you know what happens.

I'm guessing I will need a new oil pump :( I have been levering the hell outa the old one, since I'm making this engine a turbo (NA with a little turb 6-8 psi) I was thinking I should get the turbo oil pump anyway yeh?

 

Also could anyone tell me what an RB25 head (non vvt) with all the valvetrain, rocker covers, intake and throttle body would go for?

I have been offered all that for $400 but wouldn't know if it was cracked or damaged, what do you think of the price?

Cheers. Nick

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DO NOT put any levers behind the gear unless you intend to replace your oil pump, even gentle pressure on the oil pump housing will distort it and cause it to fail.

 

There is a very easy way to get them off, takes me about 30 seconds.

Get a drill about 8mm (5 16ths) and drill into the gear directly above the key slot evenly between the key slot and the teeth on the outer edge.

 

Mark the drill with a pen or put some tape on it to indicate how deep to drill, drill in till you are 'just' about to drill right through it.

Then with a reasonable sized chisle, hit the outer edge of the gear, between 2 teeth, directly above the hole you have drilled, the gear will crack straight through between the teeth, through the hole and into the key slot, they then just slide right off.

A new gear is inexpensive and having stripped 100's of RB's I have found this the best way to go if they don't just slide off by hand.

 

Hope that helps,

Rob

 

Good stuff rob.

Do you have a part number for the new gear and the rear main seal for the RB30 as well!?, and any crank related parts that go on there, other than the bearings?

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rob, that exactle what I needed, a PROVEN technique, I wouldn't have thought of that. I will definately do that tomorow and let you know what happens.

I'm guessing I will need a new oil pump :( I have been levering the hell outa the old one, since I'm making this engine a turbo (NA with a little turb 6-8 psi) I was thinking I should get the turbo oil pump anyway yeh?

 

Also could anyone tell me what an RB25 head (non vvt) with all the valvetrain, rocker covers, intake and throttle body would go for?

I have been offered all that for $400 but wouldn't know if it was cracked or damaged, what do you think of the price?

Cheers. Nick

 

You act like the method I used was an imaginary one. Worked for me. Only took a little longer to drill a second hole. Tapping doesn't take long. Must be a down under connection that makes rip's post suddenly feasible. Although a good idea.

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Finally got the little b#*stard off, Rob I did you idea and it worked a treat. I had to give it quite a few big hits but I ended up being able to slide it off with a tyre iron after it cracked, wish I had known that before ruining my oil pump. aah well it's off now so the crank is out and the front cover/oil pump.

Now the blocks ready for an acid bath, bore and hone, deck and tunnel hone.

Then I get to start putting things back in, I'm a bit worried about setting the cam timing back up but I'll do some research on this site and ask some stupid questions when things come up.

Thank you all very much for your help it made all the differance, from the sound of it a few people may have learned a couple of things from this thread so thats always good.

Cheers again. Nick

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Finally got the little b#*stard off, Rob I did you idea and it worked a treat. I had to give it quite a few big hits but I ended up being able to slide it off with a tyre iron after it cracked, wish I had known that before ruining my oil pump. aah well it's off now so the crank is out and the front cover/oil pump.

Now the blocks ready for an acid bath, bore and hone, deck and tunnel hone.

Then I get to start putting things back in, I'm a bit worried about setting the cam timing back up but I'll do some research on this site and ask some stupid questions when things come up.

Thank you all very much for your help it made all the differance, from the sound of it a few people may have learned a couple of things from this thread so thats always good.

Cheers again. Nick

 

Hey man, no worries about the cam timing, we'll sort that out when it comes to that point =)

 

You and i both! as we're just about in the same time-frame of the build. my block has just been acid bathed, and will be bored next week =)

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