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95_190_PS_PS
03-20-2012, 05:19 PM
I'm working on swapping my LT1 engine with a cracked cylinder wall. I have the engine stripped down to the block and the replacement engine sitting in my back yard right now. I'm not sure if I want to build a platform to raise my engine hoist up of if I should borrow my neighbors pickup truck and lift from the bed (I'm sure I'll get hell for even having that idea).

I have a few questions at this point...does anybody know if there is any gasket or seal between the engine and transmission that will need to be replaced when connecting the powerslot trans to the new engine? Aside from cleaning the bilge out while the engine is out, is there anything else that is recommended? I've read about repacking the shaft stuffing, I'm not sure if it is necessary or not, since I haven't ever had the boat in the water and don't know the drip rate.

On the Northstar distributor, I have a pretty badly rusted spark plug wire connector (I don't know what it's called, so I'll attach pictures). The best solution seems to be to replace the individual coil, the question is will there be any issues with having one new coil and 3 originals from 1995? The replacement coil looks to be part number "DEM GN10123" which I can order from Napa or Autozone...I just want to make sure I get this boat running the best it can.

It also seems like the aluminum honeycomb panel aft of the engine needs to be replaced as well, it is pretty spongy, or at least not firm anymore. Is replacing it with marine grade plywood coated with fiberglass resin the way to go, or should I attempt to find more aluminum honeycomb?

Thanks for any advice.

Dan

mikeg205
03-20-2012, 06:01 PM
Great thread...keep the pictures coming...I'm sure you'll get and answer from someone.

pram
03-20-2012, 06:30 PM
Can you clean up the post?

and if so, will the plug wire still firmly snap on?

95_190_PS_PS
03-20-2012, 07:05 PM
Can you clean up the post?

and if so, will the plug wire still firmly snap on?

After a few minutes with some fine sandpaper, most of the rust is off, I'm sure that the wire will still snap on firmly, this seems like it would work fine as a temporary fix. What concerns me is that the rust will come back quickly...after something starts rusting, it seems like it will just keep coming back. I can't imagine how cylinder #7 was firing with all the rust on the post, I can only assume that the added resistance would hurt the spark.

When I ran my compression test, cylinder #7 had the highest at 215psi, 10psi higher than the next highest. I wonder if a lack of spark could have possibly minimized wear in that portion of the engine.

mikeg205
03-20-2012, 07:16 PM
Put some dielectric gel on it for a good connection. 10psi difference...I would say that's in spec... the engine pro's will confirm or correct....

pram
03-20-2012, 07:17 PM
The rust is an easy issue re-occurrence

Vaseline , the lube that keeps on giving, will keep that rust away

pram
03-20-2012, 07:18 PM
I would think that lack of spark would have had a negative effect on compression. Excess fuel not being burnt causing piston wash???

now ten percent higher than the next? what were all the cylinders?

95_190_PS_PS
03-20-2012, 07:26 PM
Put some dielectric gel on it for a good connection. 10psi difference...I would say that's in spec... the engine pro's will confirm or correct....

10psi is definitely in spec, that however was between the highest pressure and the next highest. here are my results averaged over 5 tests.
#1 205 #2 165
#3 190 #4 205
#5 205 #6 195
#7 215 #8 180

The manual says that the compression pressure should be between 200 and 225 psi, and calls for a variation of 25% max between highest and lowest and if my math is correct the minimum allowance would be 161psi for the lowest pressure. However a 50psi variation seems like it should be out of specs. The numbers on the left side of the engine seem respectable, but the issue is definitely on the right side. I saw the crack in #2, but #4 fills up with water when the engine runs, so I don't know exactly what the engine issue is. Fortunately, I have a replacement ready to go in.

95_190_PS_PS
03-20-2012, 07:51 PM
Buying the boat with 1700 hours and water in the oil, I knew that it had some issues, I hoped that swapping the exhaust manifolds and risers would have fixed it, and thought that I could get a year or two out of it before the rebuild. There was rust all around on both the manifolds and risers on the left and right manifolds and risers. When I pulled the risers and manifolds, the water jackets were in poor shape, almost looking clogged with crap. After replacing the manifolds and risers and still finding water in the oil, I pulled the heads to find that they were in even worse condition. The previous owner said that he had the heads pulled and checked at a machine shop, I imagine now that he was full of it since he said he had put less than 1 hour on the boat since having them checked and they seem to be clogged, both the left and right side. If they were checked, I imagine the crap would have been cleaned out of the water jacket. I got a good deal and knew that there were engine problems when I bought it. I also knew that the previous owner wasn't all there when he wouldn't return my calls requesting him to sign the trailer registration over to me which was missed in the original sale (Florida DMV helped me out with that one).

mayo93prostar
03-21-2012, 01:28 PM
Regarding the floor panel, I had same problem with my 93 and I replaced it with plywood and epoxied over the plywood and then glued new carpet over that. It works well. the aluminum honeycomb is expensive at over $300 per 4x8ft sheet.

learjet2230
03-21-2012, 03:18 PM
Regarding the floor panel, I had same problem with my 93 and I replaced it with plywood and epoxied over the plywood and then glued new carpet over that. It works well. the aluminum honeycomb is expensive at over $300 per 4x8ft sheet.

Im gettin ready to do the exact same thing!

gotta_ski
03-21-2012, 06:07 PM
Can you post up a bunch of pics of the various internals of your engine(s)? As a fellow LT-1 owner I'd love to get a look at guts of one. I'm thinking the valve train, crankcase, and anything else you have a pic of. Thanks.

95_190_PS_PS
03-21-2012, 06:15 PM
Can you post up a bunch of pics of the various internals of your engine(s)? As a fellow LT-1 owner I'd love to get a look at guts of one. I'm thinking the valve train, crankcase, and anything else you have a pic of. Thanks.

I'll take/post a bunch of picks of the swap, and engine guts. Hopefully I can find the time this weekend to get it all done. I imagine I'll get the old engine out without a problem and run into issues with something on the install and have to wait a week or so for some random part. I'm not quite sure how to swap the trans over yet and figure I'll find my delays there.

1redTA
03-21-2012, 08:16 PM
76622

here's one when I swapped valve springs in my LT1 car


---
I am here: http://tapatalk.com/map.php?szfw3n

mattb
03-21-2012, 08:25 PM
Can you post up a bunch of pics of the various internals of your engine(s)? As a fellow LT-1 owner I'd love to get a look at guts of one. I'm thinking the valve train, crankcase, and anything else you have a pic of. Thanks.

+1 for pics

95_190_PS_PS
03-21-2012, 08:49 PM
Before I pulled the heads, there was a lot of play in quite a few of the rockers, to the point that I was able to slide them off of the valve rod. It didn't seem like it was supposed to be that way to me, more like the bolt compressing the spring should have been tighter to get rid of the excessive play, I'm guessing that 1700 hours of wear caused this, and I'm better off with the heads that came with the replacement engine and porting/rebuilding these.

95_190_PS_PS
03-21-2012, 08:54 PM
Here is the intake manifold removed, if anyone wants, I'll pull the plate off of the inside to get a better idea of what goes on in there.

EricB
03-21-2012, 09:03 PM
First, there is no gasket between the trans and the engine. No worries there.

Second, if the heads (pictured) were removed from the original engine, they must of had work done to them before. They should of been painted black.

95_190_PS_PS
03-21-2012, 09:37 PM
First, there is no gasket between the trans and the engine. No worries there.

Second, if the heads (pictured) were removed from the original engine, they must of had work done to them before. They should of been painted black.

That's good news about the heads having had work in the past, I was really thinking the previous owner was full of it with how clogged the water jackets were, since removing the heads, the clog has become more and more chalky as it dried out, and at this point falls apart really easily.

Also, thanks for the good news about the lack of a gasket, I might actually stand a chance of completing the swap this weekend. The last two weekends were a wash, my neighbor rented his house out for Daytona bike week, and the guy that rented the house completely blocked in my yard with cars and trailers...didn't see him at all the 10 days he was there, now that he's gone I get to park my bike in my neighbors garage again and have access to the engine I'm hiding out back.

gotta_ski
03-22-2012, 05:45 PM
What is the pan looking part on the bottom of the intake manifold? And yes, please pull off the plate to let us see inside. Its snowing here in Spokane so this is as close to boating as I can get right now.

95_190_PS_PS
03-22-2012, 05:57 PM
I figured that the pan was just to direct air out the intake ports evenly...I was wrong. I just pulled the pan off, only to find that I need buy a new tool to continue pulling the manifold apart.

gotta_ski
03-22-2012, 07:56 PM
Someone must know what that pan is for. Some sort of splash guard from the lifters and rods? Thermal insulator? Flux capacitor?

95_190_PS_PS
03-22-2012, 08:25 PM
It would be a waste to have a flux capacitor...our boats will never hit 88 miles per hour! I'm guessing 1redTA will be around eventually to fill us in.

learjet2230
03-22-2012, 08:43 PM
im thinkin its some kind of heat shield

1redTA
03-22-2012, 08:53 PM
it's a heat shield to lesson oil soak on the manifold.

gotta_ski
03-23-2012, 05:07 AM
This is a nerdy moment, but how cool is it that there are 3 different threads relating to the LT-1 that are active in the last 12 hours?