'96 GT40 head replacement step by step?

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   All, I've gotten good info from a number of you in the "old block new heads" thread.

I've ordered my new GT40P heads from Clearwater, and am working on gaskets, getting Liquid Wrench for the exhaust bolts, etc.

Has anyone pulled/replaced the heads on a GT40 (with MPFI)?  I will take a lot of pictures, label everything, etc.  However, if someone else has done it (as opposed to putting GT40 heads on a carb 351) and have any tricks, list of steps (best order, what to take off, what doesn't need to be taken off, etc.), that would be great.  I've been looking at the engine and making a list of things to do, but I don't know if I'm capturing everything or listing them in the best order (for example, is it necessary to take the top of the thermostat housing off to take the hoses that go from it to the exhaust risers, or do I just unbolt the whole housing from the head?), do the throttle and shift cables get in the way?), etc.

I plan to start in about two weeks (should have the heads, gaskets, and new hoses, etc. by then).

By the way, I don't have a torch (other than a propane one for sweating pipes, so I'm hoping I can get the bolts off without grinding, etc.

Thanks,

Gordon

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slmskrs Members Profile Send Private Message Find Members Posts Add to Buddy List Gold Member Joined: January-03-2012 Location: SF bay area, CA Status: Offline Points: 522	Post Options Post Reply Quote slmskrs Report Post Thanks(0) Quote Reply Topic: '96 GT40 head replacement step by step? Posted: January-23-2012 at 4:52am
	All, I've gotten good info from a number of you in the "old block new heads" thread. I've ordered my new GT40P heads from Clearwater, and am working on gaskets, getting Liquid Wrench for the exhaust bolts, etc. Has anyone pulled/replaced the heads on a GT40 (with MPFI)? I will take a lot of pictures, label everything, etc. However, if someone else has done it (as opposed to putting GT40 heads on a carb 351) and have any tricks, list of steps (best order, what to take off, what doesn't need to be taken off, etc.), that would be great. I've been looking at the engine and making a list of things to do, but I don't know if I'm capturing everything or listing them in the best order (for example, is it necessary to take the top of the thermostat housing off to take the hoses that go from it to the exhaust risers, or do I just unbolt the whole housing from the head?), do the throttle and shift cables get in the way?), etc. I plan to start in about two weeks (should have the heads, gaskets, and new hoses, etc. by then). By the way, I don't have a torch (other than a propane one for sweating pipes, so I'm hoping I can get the bolts off without grinding, etc. Thanks, Gordon
	Gordon '97 Ski Nautique, GT40

slmskrs Members Profile Send Private Message Find Members Posts Add to Buddy List Gold Member Joined: January-03-2012 Location: SF bay area, CA Status: Offline Points: 522	Post Options Post Reply Quote slmskrs Report Post Thanks(0) Quote Reply Posted: January-23-2012 at 5:10am
	By the way, the hose from the raw water pump to the thermostat housing, and from there to the two exhaust risers is 1.25" wire reenforced hose (I assume it is standard stuff that can be purchased from the local auto parts store?). Please let me know. I don't need it to say PCM on the side of the hose. :-)
	Gordon '97 Ski Nautique, GT40

Bri892001 Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: September-27-2008 Location: Boston MA Status: Offline Points: 4945	Post Options Post Reply Quote Bri892001 Report Post Thanks(0) Quote Reply Posted: January-23-2012 at 12:33pm
	Skidim seems to suggest that that hose is 1": http://www.skidim.com/products.asp?dept=1139&val=0&pagenumber=1 Remember, you want to measure the inside diameter. I know I've seen a thread of a partially torn down GT-40, it was a project Joe in NY was working on. I don't remember seeing any pictures of it going back together.

Bri892001 Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: September-27-2008 Location: Boston MA Status: Offline Points: 4945	Post Options Post Reply Quote Bri892001 Report Post Thanks(0) Quote Reply Posted: January-23-2012 at 12:40pm
	Also, I think Gun-driver has already gone through the process you are about to embark on. You may want to post a note in this thread, and he should see it: http://www.correctcraftfan.com/forum/forum_posts.asp?TID=21246&title=tearing-down-a-gt-40-mp-efi

Jllogan Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum Member Joined: May-18-2011 Location: canton, OH Status: Offline Points: 1728	Post Options Post Reply Quote Jllogan Report Post Thanks(0) Quote Reply Posted: January-23-2012 at 12:43pm
	oh I dont know if anyone ever answered you but the bolts on the exhaust manifolds are 5/16. I checked last night.
	1986 Ski Nautique 2001

storm34 Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: November-03-2008 Location: Dexter Iowa Status: Offline Points: 4492	Post Options Post Reply Quote storm34 Report Post Thanks(0) Quote Reply Posted: January-23-2012 at 1:47pm
	1" on the hoses. We replaced cracked GT40s with a set of P's last winter. Unfortunatley, we didn't do the work but did notice an increase in RPM. It was really a bummer to HAVE to buy a new prop in the spring!

slmskrs Members Profile Send Private Message Find Members Posts Add to Buddy List Gold Member Joined: January-03-2012 Location: SF bay area, CA Status: Offline Points: 522	Post Options Post Reply Quote slmskrs Report Post Thanks(0) Quote Reply Posted: January-23-2012 at 6:42pm
	Thanks all. Appreciate the confirmation on the hose size (I'll check the ID with calipers when I pull them but will assume 1" for now and see if the local auto parts place has wire-reinforced hose). As for the exhaust bolt size, someone had mentioned that they might be 5/16, so I bought a set of hex sockets with a 5/16" and confirmed it was the right size. But thanks for checking. I appreciate it. I'll check the other link to see what happened on their GT40 head replacement. As mentioned, I will take lots of pictures and will write up step-by-step instructions as I go in case someone needs it in the future (and in case I have to go in again and do something...).
	Gordon '97 Ski Nautique, GT40

snipe Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: July-13-2009 Location: United States Status: Offline Points: 157	Post Options Post Reply Quote snipe Report Post Thanks(0) Quote Reply Posted: January-23-2012 at 9:42pm
	I have my raw water pump here at home (boat is up north) it is a Ø1.00 on the inside. Might be a little tough to get it over the ridge on the pump flange, but Ø1.25 would be too large. I would stay with the wire reinforced also so there is no danger of the hose collapsing.
	80 Ski Nautique

'96 GT40 head replacement step by step?

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