3500 Venture swap

[IsaacHayes]

Push rods are the same between 3400/lx9.

Hmm, there should be a spacer (aluminum) for the AC compressor, and yeah you can shave it down if not the right size. The bottom AC bolt boss won't bolt up, but teh AC will stay on, just might rattle a bit, so might put something like rubber sheet between the bottom bolt so it doesn't rattle....

The timing covers can be swapped too if you want to use the 3400 one for whatever reason.

[WrathOfSocrus]

I have a few pics to show my progress with the parts I was expecting to have trouble with. It seems all of the hard stuff was easy and some of the easy stuff was hard. Right now I'm waiting on back ordered parts so I have been running around putting out all of the little fires that I can now. Removing the engine was surprisingly easy, and I want installation to be equally enjoyable.

I'll start off with what I thought would be the biggest issue : engine mounts. The front mount on the 3400 has the same function as most 60* motors I have seen; it holds the top passenger mount and has holes where the A/C is located.



The top holes for the A/C compressor (bottom of the bracket) are different on the 3500. They protrude about 1/4" further than the 3400. I shaved around 1/8" off of the bracket in the pic above. I'm going to wait and grind it down a little at a time until it matches up perfectly on the new motor. I'm waiting on parts before I can mount my heads and start test fitting the pieces before I shave any more off of the mount, but It looks like it will work. I measured everything out and see no reason why all three A/C bolts wont work. I have heard of issues with the bottom bolt not lining up but from what I see that should not be an issue. With the 1/4" taken off the back of the bracket to mate up with the 3500, the front of the bracket should be oriented exactly like the 3400. The bolt hole on the oil pan seems to be in the same spot on both engines.



Here is a comparison pic of engine to trans brackets. The left is from the 3500 in a G6 and the right is off of my '89 Cutlass Supreme. They are very similar but the holes are slightly different. The next picture will tie this all together.



Here we find that the Venture bracket is completely different from the others. The two brackets from the previous pic mount in the holes towards the pulley side, and those holes are in a different spot on the 3500 compared to the other 60*V6's. However the Venture's bracket mounts in the other pair of holes which are in the same spot on the 3500. If you notice it extends down and bolts to the oil pan. That bolt hole is about an inch off on the 3500. It probably would work without it but I have a few ideas to attach it. I might hack a piece of metal off of the G6 bracket so I can bolt it to the oil pan and then bolt the new metal tab to the bracket. I would have to grind the mounting boss on the 3500 oil pan down by an amount equal to the thickness of the piece of metal I am adding. I had other ideas but I don't want to put a hole in the oil pan or have to get a nut welded to the pan if it can be avoided.



Finally, someone mentioned a possible issue with the cam sensor. As I recall, even though the cam sensors can be different from motor to motor, the output is the same. The pic above shows the plug coming from the wiring harness on the right. For some reason they snaked that thing around the head on the tranny side and then ran it towards the cam sensor. The middle connector is the existing 3400 connector that leads to the cam sensor. On the left I have the 3500's cam sensor sitting there. The only difference between the two connectors is the little notch in the 3500 sensor. Looks easy enough to modify the male connector to fit in the sensor. All I had to do to the connector to make it reach was pull it back from wrapping around the head and pull about 3" of the wire out of the loom. Twist it, tape it, loom it all up and I think it will work.

There are a few other things that really could use a few hundred bucks thrown at it, like a new crank pulley and get the heads machined flat, but right now I'm out of cash to spend. Good thing I got $300 of groceries last week. I have no idea how long the parts i need will be on back order so hopefully I will be able to get everything done right and done soon.

[WrathOfSocrus]

Totally Awesome!!! I started to put the rotating assembly back together on the 3500 bottom end and made an important discovery. I was going to try and put the crank pulley bolt in to aid in rotating the motor when I noticed the end of the bolt was stripped. I look inside the crank snout to find an equal amount of damage. I have no idea how it is even possible to cause such damage, but I am totally screwed. A new crank from the dealer would be more than just buying a new 3500. No one in their right mind would part with a good crank if it has a good block to go with it.

I guess I can take the crank out and see if a machine shop can find some way to fix it, but no matter which route I go it is going to be expensive. I spent every last penny to my name and I have no idea what to do now. My mother was depending on this thing getting running in the near future and now I get to tell her that all of the money was a complete waste. She was looking at getting another car I guess I will have to save up my money and pay her back for her bad investment.

[bszopi]

You may be able to just chase it out with either a thread cleaner or a tap. I've done that before and it worked just fine.

[WrathOfSocrus]

It probably wouldn't be hard to do but I don't have anything to chase the threads with. It's only the very end of the threads but it is enough so it will not grab. The bolt looks like someone handled it rough, as if it had already been attempted to be put together, unsuccessfully. I'll have to call some machine shops around here and see what they can do for me to get the heads resurfaced and look at this crank.

[bszopi]

Going out and buying a tap is a lot cheaper than buying a whole new crank or machine shop work.

[Superdave]

i had the same problem, the damage was done from my balancer puller.

i picked up the propper tap and fixed it in 2 minutes.

[gp13069]

get the right tap and tap it out . save you a lot of time and money(: just take your time and go slow(: