3937 Winter Work

[opethmike]

Why not just remove the fuel distributor? It's only on with three screws. Remove it, be careful with the plunger, and you'll have a much easier time cleaning up the mixture unit thoroughly.

[DMC-81]

Why not just remove the fuel distributor? It's only on with three screws. Remove it, be careful with the plunger, and you'll have a much easier time cleaning up the mixture unit thoroughly.

Good suggestion Mike. In my case, the car was running pretty well before disassembly. I wanted to minimize any chance of messing anything up, so I opted to leave the FD in place.

[Jonathan]

Basically the exact same logic as what Dana just said. It was fine before I started and I'd rather not push my luck.

[opethmike]

Fair enough, but in my opinion, I think there's a bigger chance of messing up the fuel distributor by leaving it on. But hey, to each their own

[Jonathan]

I hadn't realized that the air going through the intake manifold crosses over from the RH to LH side as it enters at those two square-ish openings which the W-pipe connect to, to where it actually enters each cylinder.

The air coming in on the RH (passenger) side, goes down and across to the LH (driver's) side and feeds cylinders 4,5,6. The air then entering on the LH side, crosses over as it goes down and enters in to cylinders 1,2,3.

Must have been a matter of just physically getting everything to fit well into a small space as I don't know of any other reason why that would have been done. Anyone else know? Is it to purposely put some obstructions or channels in the way to either slow down the air speed for some reason or make it harder for some foreign object to fall directly in?

I don't think I would have noticed until when I was cleaning it and shone a flashlight into one of the openings just to double check for any debris left inside and I didn't see the light come out of the port I thought it would.

[opethmike]

Doing it side to side like that actually isn't a rare thing in intake manifold design. It allows for longer runner length, which is better for torque at lower engine speeds.

[Jonathan]

My engine is back together again. Did all the pre-flight checks for leaks or loose fittings or connections and then restarted the engine. Booya! She's running nice and smooth, idling well, and I think I came out of all of that on the other side in just fine shape.

IMG_1483.jpg

I allowed the fuel pump to prime a number of times before trying it initially. I think it cranked a couple tries first before initially catching. Then maybe two or three times it started, but died soon after. On about that 3rd try, it started and stayed running.

I did see a couple fuel leaks developing though once it had been running for five minutes or so. All connections at the distributor. Cylinder 1, 2 and the CPR connection that's down the left side just in front of the double, large return connection. They were "weeping" and not spraying, almost like you could see the metal darkening slightly but no dangerous, high pressure jet coming out.

I shut the car off, let it cool down, wiped the area and I think I even waited until the next day to tighten them a little further. I recall some advice with copper washers on these fuel lines is that any imperfections are to be somewhat absorbed by the softer copper metal, as opposed to the other way around. And to tighten it slightly beyond the recommended amount, then back it off, and then tighten back to where it was, giving the copper the chance to form around the part it wasn't sealing against. Some combination of that worked as they aren't leaking anymore. Don't really care what the book says you should do as the book isn't always very practical, so any gurus out there can zip it.

I also then got the chance to remove the jumpers I had on the backside of the Lambda ECU since two seasons ago I knew I had an electrical connection problem with the thermistor in the coolant distribution pipe in the valley. That was one connection I ensured was good when I was in there and so I was very pleased to see that once removed, the engine not only didn't zoom up to an idle stuck on 2,000 RPM like it has been doing prior to the bandaid jumpers, but it wasn't shuddering at all. I suspect this fix should have been a lot more temporary than I used it and I'll be excited to get the car out in the Spring to see how the performance and gas mileage has improved.

A couple things I found which I'll share that may be helpful for others doing similar work on their car.

The intake manifold removal instructions I got were great, but while written for a manual trans car, they omitted at least one additional vacuum line connection we have on automatics. My car has two connections on the driver's side of the intake and one on the passenger side. The small one on the driver's side is what goes down to feed vacuum to the thermal control valve. The larger one on the driver's side not mentioned in the how-to is what goes down the side of the transmission to the vacuum modulator. The large one on the passenger side is what connects through a short (7") vacuum hose to meet a "tee joint" and I believe this is where one half of that tee goes forward to the brake booster.

Something else handy I found was in regards to early cars having a slightly different routing of the engine harness. Mine is one of those early harnesses, and while I'm not sure how much better or out of the way the late style ones are, the one I have can very much get in your way as it dangles above the valley when you're working. It can also get tangled or caught up when you try and snake the intake manifold back in place as well as the mixture unit. What I did was use a short bungie cord, that grabbed (gently) on to a meaty section of the harness and then I looped the other end of the bungie cord to the metal hanger rod along the firewall. This pulled on the harness just enough to keep it out of the way and let you work around it.

Shown here:

IMG_1438.jpg

Any of you that have cleaned out the little grid of pockets on the top of the crankcase know how deep a couple of those go. My normal vacuum cleaner extension wouldn't get in deep enough because even the smallest attachment I had was too wide. I kind of MacGuyver'ed what would almost be a child's pen or marker that I removed the writing parts from the inside and basically used as a very thin but firm tube to carefully slip down into those recesses and suck up what was in there the best I could. I'm sure you've all come up with your own solutions.

Last thing I found was how important the orientation of the hose clamps can be on certain coolant hoses in or near the intake and valley. The two I found that were causing me unnecessary problems getting my intake out initially and then back in, were the ones just in behind the water pump/thermostat assembly. If you can imagine all things removed, so you are looking down with an unobstructed view of that assembly, the hose clamps were on so that your screw driver you would point straight down and on the INSIDE of the thermostat. The problem with this is that the intake is a tight enough fit when it gets back to close to the electrical distributor, that if you cost yourself even only half an inch of less space with bad hose clamp positioning, it can make it a real bugger to try and get the intake manifold down and into place.

I started to see how this was much harder to get in than I felt it should be. Dave S.'s advice from years ago was to stop if something plastic or otherwise just won't go in. Stop and look why and don't keep forcing it. I knew the clamps needed to be spun at least 90 or 180 degrees and I was able to do this without spilling any coolant. Once out of the way and having the space I should have had, it went in nice and easy.

And that was that.

[opethmike]

Gurus? I don't know of any gurus around these parts

[Bitsyncmaster]

I've "MacGuyver'ed" a smaller hose onto my vacuum a lot of times. Usually just find some junk hose and tape it to the vacuum hose.

Glad to hear your back up and running and have fixed some of the problems.

[Rich_NYS]

Awesome.....lookin' good!