3500 swap questions

[wasas9]

ill let you know next week dave.

[Superdave]

Does anyone think it's possible that the stock 3500 CTS is calibrated differently than the stock 3.1 CTS?


I ask because my 3500 gets to operating temp pretty fast.. then averages about 3/4 up the gauge which should be just over 200F.. the thermostat is actually 180F and my fan turn-on temps are set there as well...

in my stock 93 3.1 the same exact cluster and the car hardly gets to 1/4 gauge with a 195 thermostat.




I guess i can try to rig up an old 3.1 CTS in the system somewhere... maybe in the heater core lines or something...

[wasas9]

Where did you order the adapter from? Does it look like coolant will be able to flow around the sensor at all? Will the sensor "probe rod" part that sticks out even fit into the adapter?

Don't know for sure, but i assume coolant will flow in and out decent enough for a good read.

I bought it at a local Car-quest auto parts store. The guy at the counter was really surprised that they even carried that kind of adaptor lol.

update with pics. adaptor cost 13$

[3400-95-Modified]

Exactly... This is why I put a 3400 under my 3500 parts... Remember I bought both complete motors for under 500 bux, with only 4k on them... I had the opportunity to drop in a 4k mile 3500, but with these changes/problems I said F-it, I'll stick with the lower end that I KNOW works with no issues... since this is my daily driver and all. Car was only down for 2 weeks during the swap because i blew the old motor... swap only took 1 day though.

[PCGUY112887]

Then I guess it's a 3500 thing :-/

[3400-95-Modified]

the head sensor is M12x1.5 thats what I had my sensor re-cut to.

Oh and my trans bracket did not have those problems. Mine lined up perfectly...

Its my AC compressor hole on the 05 3400 oil pan that is slightly out of wack in comparison to a 95. or a 01 for that matter.

[PCGUY112887]

Where did you order the adapter from? Does it look like coolant will be able to flow around the sensor at all? Will the sensor "probe rod" part that sticks out even fit into the adapter?

[wasas9]

hey, just some new info I got about the coolant thread type. It is not the 1/4" SPT as you stated earlier. I have the correct adaotor on order. It is a 12 mm by 1.5 or something. Ill let you know exactly what it is.

[bszopi]

Can't use an older pan on the 3500 block, as there is 1 bolt hole that is in a different location, as well as the oil pan being notched for the rods. So you'll have to adapt the bracket to work.

[PCGUY112887]

OK, more info.

DOHC fuel injectors - easy way to use them with the 3100 clips, just take a hack saw blade and very carefully extend the little groove around the injector... stock the groove only goes 3/4 of the way around, but on 3x00 injectors it goes all the way around. A tiny bit of work and the clips will fit on your DOHC injectors like a dream.

OK now for the bracket...



Almost impossible to get it into focus at the angle I was laying, but you can make out what the problem is... it's close but no cigar.



Where the bracket bolts to the oil pan... it must be a newer pan thing if 3400-95-Modified's 05 pan does it too. I probably could have just put on my 3100 oil pan so I would get the oil level sensor in the bottom of the pan, and the bottom bracket hole would line up... but oh well too late now.

Any good ideas on getting that thing to work? I could beat on the bracket but damn seems like an aweful lot to beat, that bracket is fairly strong. What about the bracket from the newer engines? What do they look like?

I am also in the middle of splicing the 3500 MAP sensor connector onto my 3100 wiring harness so I can use the 3500 MAP... I wanted to ensure I had the wire colors right (if anyone happens to know).



The wires I am holding are from the 3500 map sensor plug.

Thanks.

[3400-95-Modified]

My third doesnt fit without slight mods to the compressor... 05 3400 oil pan, And I wont do that till I replace it.

But if you think about it all the force on the compressor is pulling towards the motor so its not like those bolts are holding it from being pulled way from the motor.

I haven't had any issues yet

[IsaacHayes]

LOL Jon, lost your 3rd bolt or something? I'd worry about the A/C but I guess it could be ok since there are 2 top bolts and they go into steel. It would not be hard to fab a spacer/adapter type thing I would think for the 3rd bolt. Maybe even without a welder.

[3400-95-Modified]

You need to bolt that rear trans bracket down somehow, it prevents the trans from flexing back away from the motor...

Also the AC compressor Mine currently has only 2 top bolts in it, so no worries on that.

[Superdave]

Pics?


I beat up my 3.1 rear mounts pretty good to make them fit.. took a few hrs of work.

[PCGUY112887]

You guys must be sick of me and my engine noobness :P

I finally got a bolt in the top of the tranny... a slightly shorter one than original. I had to take a hammer and force it in, put a good scratch on the header but I got it in there and torqued it good.

My new problem is this rear engine bracket that goes between the tranny and block... all 3 holes in the block are close to mounting but not quite there... I would have to do some serious work to the bracket to make one work right.

However right now I have the bracket bolted to the tranny and it is VERY tight against the mounting bosses where it's supposed to bolt to... I can't decide exactly what kind of force is put against it... so I can't decide if I want to try to just leave it with no bolts or fab up some sort of bracket. I am afraid it may hit the block some if I leave it, maybe giving false KR and who knows what else...

Also the AC compressor, well the 1 bottom bolt does not line up on the 3500. I could have swore it did, I measured it out before I even got the engine but now it doesn't want to fit, bottom bolt is about half of an inch or so away from threading in. Anyone ever run a compressor with only 2 top bolts?