I am trying to install a 1969 350 engine with carb and distributor attached into my 86 Trans Am. I have it close, but not final. I'm about 4-6 inches from mating up with the T5 transmission bell housing with the shaft in the pilot bearing hole. However, I cannot slide the engine back any further, since the motor mount brackets on the engine collide with the motor mounts on the cross member. The transmission is jacked up and touching the firewall, so I can't raise it up any further. Is it a matter of refining the engine angle to clear the mounts, or do I have to remove the mounts? I removed the 305 without removing the motor mounts, so I thought I should be able to install the 350 without removing them.

 

Move the transmission as far forward as it will go; unbolt it from the crossmember and move it forward. Put a floor jack under it if necessary. Mate the engine and trans in that position first, then continue to lower the whole thing into place as you slide it rearwards.

Probably would help to get that dist out of there; less chance of destroying it when it hits the firewall.

No need to remove the mounts.

 

The other option is to unbolt the transmission from the crossmember or just unbolt the crossmember and slide the transmission back. Drop the engine into place then slide the transmission up to the engine.

 

Can I move the manual transmission enough, without removing the shifter/console stuff?

 

Ok. The engine is installed, thanks to your input. I disconnected the clutch slave cylinder from the bell housing. I disconnected the drive shaft at the rear u-joint and structural truss from the differential and let them hang down. I removed the center console and shifter from the top of the transmission. I disconnected the transmission cross member (under the transmission mount), lowered the transmission on a hydraulic jack, and moved it back under the car (on jack stands), far enough away from the engine compartment to lower the engine onto the engine mounts without hitting the bell housing. I left the distributor in place. It would have been safer with the distributor removed. I did remove the exhaust manifolds, down pipes and "Y' pipe. Next, I'll reinstall the transmission and drive line. It looks like the e-bay headers are going to fit, but I'll have to remove the spark plugs and heat shields first.

 

Ok. More to report. I got the transmission and drive line all back in place. The intermediate length headers did not fit. The clutch slave cylinder interferes with the header collector on the driver side, and the header collector on the passenger side is touching the metal fuel lines. I could easily reroute the fuel lines a bit higher, but since the driver side wouldn't fit anyway, I opted to buy Ebay shorty headers. They fit perfectly. but as with many of the headers out there, not all of the holes line up perfectly. I had to file out two holes in each header flange about 1/8" to bolt up the headers. Since the other bolt holes lined up perfectly, having two holes a little oval didn't cause any problems.

 

Next issue is a simple but frustrating one. I cannot seem to find the ignition wire that goes to the starter. Everything I research and everyone I ask says its a purple wire from the ignition switch through the firewall to the starter. Basic enough, I found a heavier gauge purple wire that goes toward the right front engine compartment (no where near the starter), and I found another smaller gauge purple wire that goes in that same general area, but no purple wire coming out of any harness over the bell housing near the starter. Is there some way to trace the correct wire from the firewall? Where should I start?

 

B4 of c100 maybe

 

I don’t know what that means. I just can’t find where the purple wire comes through the fire wall.

 

C100 is the bulkhead connector next to the master cylinder.

 

Here is a 87 pinout should be close to yours


http://www.austinthirdgen.org/mkport..._1987_C100.gif

 

I found the purple wire. It’s a heavier 12 gauge wire. But it is in a wiring harness that goes all the way to the battery, instead of the starter terminal.

 

I have installed the cable from the battery negative terminal to the alternator bracket, the wire strap from the negative battery terminal to the body close to the battery. What all is supposed to be connected to the positive battery terminal? I have installed the cable from the starter solenoid to the positive battery terminal. The wiring diagram shows a black wire from the positive battery terminal splitting into a black/red wire going to the alternator and an orange fusable link going to the computer command control. There is a red wire plugged into the alternator that came with the 69 engine I bought. I have not attached it to anything else, yet. I have a marine style positive terminal, so I can easily add wires to the positive battery terminal. I assume I should attaché the red alternator wire to the positive battery terminal and see if I can figure out which wire is the orange fusable link. Does this all sound correct?

 

Ok. I'm back. A lot has happened since my last post. I replaced the coolant temperature sensor (located towards the front of the driver side of the engine just below the header flange). I also replaced the coolant fan sensor/switch (located towards the rear of the passenger side of the engine just above the starter). The threaded sensor holes in the 1969 350 block are larger than the sensor holes in the 1986 305 block, so you have to use an adapter for the new 1986 compatible sensors. The correct sensors and adapters come in kits available on the internet for a lot less than local auto parts stores. I used a 1986 Trans Am wiring diagram to trace the colored wires from the relays (located on the driver side of the fire wall). I tested the electric cooling fan by placing the black wire on the negative battery terminal and placing the black/red wire on the positive terminal. Note that, if you switch the wires, the fan will turn in the opposite (wrong) direction. After installing the new sensors, I tested the coolant temperature sensor wire (that goes to the coolant temperature gauge) by turning the ignition key to the "on" position and touching the wire at the sensor to ground. That caused the temperature gauge to "peg" all the way to "hot". That way I knew I had the right wire attached to the coolant temperature sensor. Likewise, I tested the wire attached to the coolant fan switch (that goes to the coolant fan relay) by turning the ignition key to "on" and touching the wire at the sensor/switch to ground. That caused the coolant fan to turn on. That way I knew I had the right wire connected to the coolant fan sensor/switch and the relay was working. These tests did not guarantee that the coolant temperature gauge or coolant fan switch were working at the correct temperatures. That could be tested by starting the engine and watching the temperature gauge, and by looking for the temperature at which the fan comes on and goes off to see if it comes on and off at the correct temperatures. Well, that's where I am right now. The coolant temperature gauge is working properly, but the coolant fan is not coming on at all. I grounded out the wire to the coolant fan switch/sensor, but the coolant fan did not come on. If that is the correct procedure, then I suspect that the relay is bad. I did drive the car around the block with open headers. It was loud, but what a beautiful sound! Yes, it started to over-heat, but I shut it off soon enough.

 

OK, so at this point, the wire, relay, and fan are all working properly. Nothing is broken. But then sometime later:

What changed?

The stock fan switch in these cars is supposed to turn the fan on at around 230 - 235°F. Should turn off at around 205 - 210°.

If you have heads with the old size holes (½" NPT) you can use a older temp gauge sending unit; you can ask for something like 69 Chevelle 350 at the parts counter. They're electrically the same as the one with the smaller (3/8" NPT) threads in the newer heads. I don't know of any electric fan switch with that size thread but there probably is one, I just have never come across it. Or, you can go to Home Depot or Lowe's or Ace, and get a brass 3/8" - ½" bushing, which looks like this. https://www.thirdgen.org/forums/cool...ding-unit.html I'm going to guess that whatever "kit" you got has something similar?

When you "grounded out" the wire the 2nd time, what did you touch it to? Are you SURE the thing you touched it to was grounded, itself?

 

The only thing that changed was hooking up the wire from the coolant fan relay to the sensor/switch at the block. The switch I used is much cooler than the stock switch (145-175 degrees). I will test again. I should get the fan to turn on by disconnecting the wire at the sensor/switch and touching it to a good ground (header bolt), while the key is turned "on", but not with the engine started. Does that sound right? By the way, you are right about the 1/2'-3/8" adapter. They are much cheaper at Home Depot and work perfectly with the 3/8" sensors. My on-line sensor came with the 1/2"-3/8" adapter, so I returned the Home Depot adapter.

 

Yes that's correct about grounding, except that header bolts aren't necessarily the best ground in the world, what with rust and all that. You might want to try something a bit more secure, like use an alligator clip lead, and clip it from the center pin of the connector to one of the screws on the firewall right by there where other things are grounded.

And of course it's not impossible that the wire itself is damaged, like, broken off right behind the crimp of the pin; that happens unpleasantly often to such things. It's a VERY common pigtail though, the same as for knock sensors and various other things, so it should be readily available if it turns out to be farkled.

 

I grounded to the battery negative terminal, no fan. After removing and inspecting the fan relay, I noticed it had been taken apart and glued back together, so I ordered a new relay. I traced the wires from the relay to the sensor, and everything looked good.

 

New issue. I installed a new oil pressure gauge (near the distributor). When I turn the key to "on", the gauge moves slightly off zero. When I start the engine, the gauge pegs and stays there. With the 1969 350 block and the 1986 Trans Am gauge, which oil pressure sending unit/sensor/switch should I be using, or could there be something else I'm missing?

 

86 TA

No you're not missing anything. About that, at least.

The sending unit does not care about the block. All blocks expose pressurized oil to the SU. The SU does not look around itself and see what castings it's associated with; it simply responds to … oil pressure.

Sounds a little like, instead of a gauge sending unit (big bell shaped thing about 2" long and 1½" dia) you put in an idiot light switch (MUCH smaller, no bell-shaped part).

Should look about like this. https://www.autozone.com/external-en...8014_1135286_0 If it looks somewhat more like this https://www.autozone.com/external-en...-ps24/123380_0 you have the wrong part.

 

I exchanged the oil pressure sending unit at Autozone, BUT, now there is not enough room to install it. The distributor is above the port and the sending unit is about 1/2" too tall to screw into the port below. The oil pressure sending unit port on the original 305 block is above the oil filter. I have not looked to see if there is a similar port near the oil filter on the 350 block. I would rather use the port near the distributor. Is there a shorter version of the sending unit?

 

No...

It's not supposed to just go into the hole. What you need is a short extension and a 90° fitting. It's 1/8" pipe thread. You can go to the hardware store, HD or Lowe's or Ace or whatever, and buy a 1½" long 1/8" NPT nipple (looks like a short piece of brass pipe with threads at both ends), and a brass 1/8" NPT elbow. You will closely replicate the factory setup that way. Screw the 90° onto one end of the nipple, screw the other end of the nipple into the block, screw the sending unit into the 90°. Don't overtighten any of it. Use the automotive pipe thread sealer with Teflon, NOT RTV of any kind, on the threads. The sending unit should point toward the driver's side and somewhat to the rear, toward the firewall.

There is a port on a 350 in the same place as your 305; it's actually not a "port" as such, it's a hole created during the block mfg process, where they drill an oil passage from the filter to the main oil distribution point in the block. In theory you could take the plug out and use that hole but you'd need a bushing to adapt the size; and the plug is usually near impossible to get out anyway. Your best bet is to use the port in the top of the block behind the intake and get the pipe fittings as described above.

 

The 1/8" NPT fittings from Home Depot worked perfectly, but with little room to spare between the firewall and the horizontally installed oil pressure sensor.

 

I installed a new relay and made sure the wiring was correct, but still no fan. It turns out, someone had previously used a 30 amp mini fuse in the fuse box, instead of the factory standard size 20 amp fuse. The mini fuse was "blown". Once replaced with the proper 20 amp fuse, the fan worked perfectly.

 

My new question: besides any emissions related issues, does the lower cooling fan temperature range affect anything negatively? My thought was a lower temperature range would be easier on the engine and produce more horse power.

 

The next step is tuning and carburetor adjustment. I think I have choke linkage/adjustment issues. Is there any benefit to removing the choke entirely? If so, what do I need to do? I am in Mesa, Arizona, and do not plan on driving the vehicle in cold or inclement weather.