Which crank does my 90 have?

11-05-2006, 12:27 AM

Check these pics:

http://homepage.mac.com/billwilner/PhotoAlbum8.html

Thanks,

Bill

Agent935 · 11-05-2006, 12:52 AM

Looks like a short nose too me. It should be anyway unless the engine was replaced. check the vin on the block. If it matches the car it's short nose.

Also the long nose has an additional spacer that goes between the accessory drive pulley and the timing pulley.

Bryan · 11-05-2006, 04:43 PM

Long-nose. You can tell by the 8 slots in the main pulley. Check out this article for more info

Agent935 · 11-05-2006, 05:30 PM

I stand corrected!

thedishesrdone · 11-05-2006, 05:48 PM

i think the crank bolt is a different size too, i think the long nose is like a 21 or a 19, and the short nose is supposed to be a smaller head. but yeah that article on m.net will tell you.

Bryan · 11-05-2006, 06:07 PM

Quote:

Originally Posted by thedishesrdone @ Sun Nov 05, 2006 7:48 pm

i think the crank bolt is a different size too, i think the long nose is like a 21 or a 19, and the short nose is supposed to be a smaller head. but yeah that article on m.net will tell you.

I don't know what size the bolt is off the top of my head, but the long-nose has a wider shoulder.

Nevadabob · 11-05-2006, 08:45 PM

There is a larger difference between the ID of the bolt hole and the OD of the nose on the pictured crank than on the "light weight sports crankshaft" that normally is in a '90.

The first time I did my timing belt is was scary to see how thin the wall of the nose is on the short-nose crank. That said, I did 2 timing belt changes on the original '90 with no problems in 166k miles. The current '90 has the LWSC and I changed the timing belt at 90k, still running strong.

Bryan · 11-06-2006, 05:12 AM

Quote:

Originally Posted by Nevadabob @ Sun Nov 05, 2006 10:45 pm

There is a larger difference between the ID of the bolt hole and the OD of the nose on the pictured crank than on the "light weight sports crankshaft" that normally is in a '90.

The first time I did my timing belt is was scary to see how thin the wall of the nose is on the short-nose crank. That said, I did 2 timing belt changes on the original '90 with no problems in 166k miles. The current '90 has the LWSC and I changed the timing belt at 90k, still running strong.

As long as the job is done right, there's really nothing to fear. Having a long-nose crank DOES NOT protect you if the timing belt job is not done right--ask me how I know

11-06-2006, 09:00 AM

Bryan, How do you know?

Quote:

Originally Posted by Bryan @ Mon Nov 06, 2006 3:12 am

Quote:

Originally Posted by Nevadabob @ Sun Nov 05, 2006 10:45 pm

There is a larger difference between the ID of the bolt hole and the OD of the nose on the pictured crank than on the "light weight sports crankshaft" that normally is in a '90.

The first time I did my timing belt is was scary to see how thin the wall of the nose is on the short-nose crank. That said, I did 2 timing belt changes on the original '90 with no problems in 166k miles. The current '90 has the LWSC and I changed the timing belt at 90k, still running strong.

As long as the job is done right, there's really nothing to fear. Having a long-nose crank DOES NOT protect you if the timing belt job is not done right--ask me how I know

11-06-2006, 09:05 AM

The oil pan VIN matches the car, but the block has this weird stamped aluminum tag on it dated 10/24/2003, with a Mazda OEM part #B61P-02-300R.

Does anyone know what I've got here?:

http://homepage.mac.com/billwilner/PhotoAlbum9.html

Bryan · 11-06-2006, 09:05 AM

Long story short, Junior sports a Loctite-fixed crank nose.

roadsternut · 11-06-2006, 10:33 AM

The engine number cut-off for the change in crank design is B6-127441.

Block details; the part number is correct for a 90-93 engine. This plate doesn't appear to be a Mazda factory plate; I'll hazard a guess its either a reconditioned block, or one imported as a used motor. I doubt this is a NB6 block; it will be a fair bit of work tro get a Mk1 head tro fit.

speedworkz · 12-10-2006, 05:06 PM

definitely a long nose. as stated before, the 8 windows on the crank pulley are an easy tell tale sign.

as for the oil pan and the VIN # i would assume it was switched with the old motor so the numbers would match.

new crate engines from mazda have no VIN's obviously and can have the pan switched or the VIN tag rivets from the old pan drilled and re-rivetted (is that a word?) back on to the new pan.

11-05-2006, 12:27 AM	#1 (permalink)
MiataRoadster Guest Posts: n/a	Which crank does my 90 have? Check these pics: http://homepage.mac.com/billwilner/PhotoAlbum8.html Thanks, Bill
MiataRoadster Guest Posts: n/a

11-05-2006, 12:52 AM	#2 (permalink)
Agent935 Member Join Date: Apr 2006 Location: Portland, OR Posts: 1,687	Re: Which crank does my 90 have? Looks like a short nose too me. It should be anyway unless the engine was replaced. check the vin on the block. If it matches the car it's short nose. Also the long nose has an additional spacer that goes between the accessory drive pulley and the timing pulley.
	__________________ Ben ================= 1993 Limited Edition #935 PDX Cheerleader and Unofficial Organizer 1.8 Swap Project Thread http://img.photobucket.com/albums/v3.../signature.png

11-05-2006, 05:30 PM	#4 (permalink)
Agent935 Member Join Date: Apr 2006 Location: Portland, OR Posts: 1,687	Re: Which crank does my 90 have? I stand corrected!
	__________________ Ben ================= 1993 Limited Edition #935 PDX Cheerleader and Unofficial Organizer 1.8 Swap Project Thread http://img.photobucket.com/albums/v3.../signature.png

11-05-2006, 05:48 PM	#5 (permalink)
thedishesrdone Noob Join Date: Jun 2006 Posts: 43	Re: Which crank does my 90 have? i think the crank bolt is a different size too, i think the long nose is like a 21 or a 19, and the short nose is supposed to be a smaller head. but yeah that article on m.net will tell you.
thedishesrdone Noob Join Date: Jun 2006 Posts: 43	__________________ 91 miata turbocharged 90 miata with wiring issues

11-05-2006, 08:45 PM	#7 (permalink)
Nevadabob CR.net Supporter Join Date: Apr 2006 Location: Las Vegas, Nevada Posts: 287	Re: Which crank does my 90 have? There is a larger difference between the ID of the bolt hole and the OD of the nose on the pictured crank than on the "light weight sports crankshaft" that normally is in a '90. The first time I did my timing belt is was scary to see how thin the wall of the nose is on the short-nose crank. That said, I did 2 timing belt changes on the original '90 with no problems in 166k miles. The current '90 has the LWSC and I changed the timing belt at 90k, still running strong.

11-06-2006, 09:05 AM	#10 (permalink)
MiataRoadster Guest Posts: n/a	Re: Which crank does my 90 have? The oil pan VIN matches the car, but the block has this weird stamped aluminum tag on it dated 10/24/2003, with a Mazda OEM part #B61P-02-300R. Does anyone know what I've got here?: http://homepage.mac.com/billwilner/PhotoAlbum9.html
MiataRoadster Guest Posts: n/a

11-06-2006, 10:33 AM	#12 (permalink)
roadsternut Esteemed Member Join Date: Apr 2006 Posts: 1,791	Re: Which crank does my 90 have? The engine number cut-off for the change in crank design is B6-127441. Block details; the part number is correct for a 90-93 engine. This plate doesn't appear to be a Mazda factory plate; I'll hazard a guess its either a reconditioned block, or one imported as a used motor. I doubt this is a NB6 block; it will be a fair bit of work tro get a Mk1 head tro fit.

12-10-2006, 05:06 PM	#13 (permalink)
speedworkz Sponsor Join Date: Dec 2006 Location: Northeast Pa. Posts: 4	Re: Which crank does my 90 have? definitely a long nose. as stated before, the 8 windows on the crank pulley are an easy tell tale sign. as for the oil pan and the VIN # i would assume it was switched with the old motor so the numbers would match. new crate engines from mazda have no VIN's obviously and can have the pan switched or the VIN tag rivets from the old pan drilled and re-rivetted (is that a word?) back on to the new pan.

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