Nola Mike's 3.7/470 --> 4.3L swap thread

[nola mike]

Oh, I see. So new damper is ¼" shorter. If I remove the ring then I can just throw my old balancer in there. Guessing that's sitting beneath the timing cover. Think I'd rather get a new balancer with a shorter nose than remove and replace the cover if such an animal exists. And the persuasion looked more like a framing hammer. It was actual t40, but the heads got tweaked enough by the t30 to not have it go in easily.

 

[Scott Danforth]

buy a ball peen, framing hammers have a hardened face and dont do well hitting hardened tools.

 

[Scott Danforth]

Oh, I see. So new damper is ¼" shorter. If I remove the ring then I can just throw my old balancer in there. Guessing that's sitting beneath the timing cover. Think I'd rather get a new balancer with a shorter nose than remove and replace the cover if such an animal exists. And the persuasion looked more like a framing hammer. It was actual t40, but the heads got tweaked enough by the t30 to not have it go in easily.

not sure if its 1/4" or thinner. on the last motor I did, it was 1/4" off. with the damper off, look between the crank snout and the seal.

 

[nola mike]

But am I correct that the timing cover has to be removed and replaced to get to the ring? And do you know if they make a properly sized damper?

 

[Scott Danforth]

you need to verify that the reluctor is in there. the oil pan and front cover have re-usable gaskets.

 

[nola mike]

Wow, another super frustrating day. I spent most of it installing/removing balancers. Started by cleaning out the crank threads (promising start). Swapped the balancer over, started to tighten down the crank bolt, and felt it give. Crap. Looks like not enough threads engaging, stripped out the first few threads of the crank. Swapped balancers back and forth, trying to figure out why I wasn't getting enough thread engagement. Eventually pulled the timing cover and removed the CPS reluctor. Got a new cover and tried again. Same thing. I really don't understand what the issue is. But I'm only engaging about 1/4" of crank bolt threads (and now they're toast). So. Issues:

1. Balancer. I'm positive it's bottomed. I think at this point I just get a longer crank bolt and torque it down. There's plenty of room in the crank for a longer bolt. Current is 2.25", I might try 2.5 or even 2.75. I can't think of an issue with this; anything I'm overlooking?

2. Another, possibly bigger issue. I was trying to put the water pump housing on to see if the pulleys lined up (looks like it does, but who knows). The bottom of the housing hits the timing cover bolts. I was thinking of grinding the bolt heads down, but I still don't know if it will fit.

EDIT: OK, I just looked at the merc timing cover, and it appears different than the GM version, the bolts are recessed. Is that true? The pump housing doesn't look like it's changed part numbers. If so, can I use my old tin cover? Looks like another day of pulling balancers...

 

[Scott Danforth]

You need to use a balancer installation tool. Not the bolt. Go to your local FLAPS and borrow it

 

[nola mike]

You need to use a balancer installation tool. Not the bolt. Go to your local FLAPS and borrow it

I was using an install tool. The bolt needs to be torqued after the balancer is pressed on, and the bolt didn't engage enough threads. Like it wasn't long enough, or the balancer wasn't on all the way (but it definitely was... Multiple times).

 

[nola mike]

Here's a pic of the cover interference. I'm now very confused as to whether this is a standard gm cover or something different. chartersj , I saw a thread where you ran into some issues; looks like you were doing this same swap?

 

[Scott Danforth]

make a spacer......

check the part number on the water pump, could be a different one is used 96 on

 

[nola mike]

Scott Danforth , the water pump doesn't look like it has changed since '87 (which is what I originally had assumed had happened). I dont see any parts diagrams post '98, that's what I've been using. If I make a spacer then my pulley alignment will be off. Only thing i can think of is that the cover is different.
Edit: actually, pics of the gen+ engines for the cover look the same as the composite GM. So wtf?

 

[Scott Danforth]

maybe they use these https://www.mcmaster.com/low-profil...ainless-steel-low-profile-socket-head-screws/

 

[nola mike]

Well...duh, don't know why that didn't cross my mind. don't know if that's what's used (doesn't look like it), but whatever. That's a much better solution than grinding down the bolts, or removing everything yet again. I drive by Fastenal on the way to the boat, I'll see if I can pick those up. Any issues that you can think of with a longer crank bolt? The diagrams say they're 2.5", but both of mine were 2.25 (not including the head). Appreciate all the help Scott, even I'm starting to lose interest in my problems.
On the plus side, I did drop the pan yesterday and cleaned it up real purdy and new gasket. Also found my missing PS fitting is the same size as the trim line at the pump.

 

[Chris51280]

Here's a pic of the cover interference. I'm now very confused as to whether this is a standard gm cover or something different. chartersj , I saw a thread where you ran into some issues; looks like you were doing this same swap?

This seems odd. Looking at the part numbers for the pump, they are the same throughout the years. The pump is in the correct orientation? stupid question, I know.

 

[Scott Danforth]

Crank bolt is just a grade 8 bolt.

 

[nola mike]

This seems odd. Looking at the part numbers for the pump, they are the same throughout the years. The pump is in the correct orientation? stupid question, I know.

Yeah. I actually thought about pump orientation. I think there's only 1 way for it to go. I'll double check. Called michiganmotorz, they said their pumps work with everything, but weren't sure if the design had changed at some point to accomodate the composite cover.

 

[Chris51280]

The cover may be specific to mercruiser vs GM. The pump certainly is

 

[Scott Danforth]

The cover may be specific to mercruiser vs GM. The pump certainly is

the entire long block comes to Mercruiser/Volvo/Inmar/Etc from GM. cover and the water pump are GM industrial engine parts.

 

[nola mike]

the entire long block comes to Mercruiser/Volvo/Inmar/Etc from GM. cover and the water pump are GM industrial engine parts.

I was wondering that. If that's the case, then there must be a design change in the pump. Might go ahead and order a new one. Trying not to rube Goldberg this thing too much...

 

[Scott Danforth]

https://www.amazon.com/CIRCULATING-WATER-MERCRUISER-VOLVO-ENGINES/dp/B019G9AVC2

https://www.michiganmotorz.com/circulation-water-pump-p-55.html

here are two that I found