3.0L engine swap

[dn010]

Looks great! The new steering shaft and joints are next on my list to purchase/install.

[Farrar]

If all goes well, I will re-take possession of #2613 this weekend. I am very excited! It's been over two years since I last saw the car in person, and almost three since I was able to drive it under its own power. While this car was in limbo, I went back to college to finish my degree, moved from Louisiana to New York, and then moved again from New York to Florida. It's been an eventful few years.

Bill wisely told me that rehabilitating #2613 would not be a quick thing. To be compatible with the 3.0L engine, the intake manifold from the 2.8L had to be adapted. Ignition timing was handled via a camshaft swap, but it did require some machine work. And compatible accessories had to be sourced and installed, including an a/c compressor, alternator, and idler pulleys.

Then there were the things that went wrong...

- fuel tank sender failed
- temperature gauge failed
- transmission bellcrank cable failed
- transmission cooler line fitting failed
- angle drive failed
- torque converter seal failed
- engine mounts fell apart
- automatic transmission computer failed
- probably some other stuff I can't remember right now

The car is not perfect, but it is roadworthy. #2613 has a temporary temperature gauge from Jegs, and a transmission computer bypass. I will need to get started on those and other repairs when the car gets to my garage. Some interior parts are still missing. There's no radio. And there are probably a few other things that I can't remember right now. But at long last my schedule and Bill's have finally lined up and I can take possession of #2613. (Meanwhile, since its successful shakedown last fall, Bill has been driving it once every week or so to make sure it's OK.)

Exciting times!

[Lwanmtr]

Cool. I hope everything works out and you can finally get to driving her again.

[Farrar]

Cool. I hope everything works out and you can finally get to driving her again.

So do I. Not gonna lie - I'm probably just going to enjoy driving it for a little while before I start on the shift computer repair. It's great driving weather down here now.

[Farrar]

#2613 is in my garage now. We drove home today 150+ miles. #2613's 3.0L ran hotter than I would like - "normal operating temperature" seemed to be about 220°F. Otherwise everything was OK, so I drove on, but the longer I was on the interstate, the higher the temperature crept: with the a/c on it got up to 240°, then 250°. (Note: dash gauge is inaccurate, so a brand new gauge from Jegs had been temporarily installed for the drive home.) After a while, the rain stopped and the clouds cleared, and while driving in the sun the temperature gauge moved above 260°F. I turned the a/c off, but it made no difference. Not longer after the gauge started to point above 260°F, my wife (in the vehicle behind me) started blinking her lights and signaling for me to pull over because she saw what she thought was white smoke coming from the engine compartment. Coolant was spewing out the overflow tube; some of it got on the right muffler and evaporated.

We took the next exit and parked in a lot. I turned the radiator cap one click and nothing happened. "That's weird," I thought, "Shouldn't that have released some pressure?" Turned it to the second click. Eruption! LOL I was wrong. :P When things get funky, I get flustered. Oh, well.

We were 48 miles from home. Rather than drive the rest of the way in a DeLorean with a crippled cooling system, I called AAA for a free tow home. I felt safe driving it on and off of the truck and into my garage. All in all, it could have been a lot worse. (For example, the tires were manufactured in 2008 and the rears are cracking along the side of the tread.)

What happened?

Here is my theory. #2613's engine coolant was once green. It is now vaguely rust-colored. This is probably because the cylinder liners in the replacement engine are now shedding their corrosion. Although I didn't see any particulate matter in the coolant, it's possible that a flake of rust got stuck in the thermostat, causing the thermostat to fail.

Bill has a different theory. The cooling system of a 1981 DeLorean is different from the cooling system in a 1989 Eagle Premier. The engine may have a higher-temperature thermostat, which was fine in the Eagle but not in the DeLorean. This means that the Eagle thermostat does not play well with the DeLorean's radiator and other components. The problem was made worse by the fact that the fan shroud on #2613 has crumbled to dust.

Either way, I'm replacing the thermostat. But with what?

If I plug the 1989 Eagle Premier into the AutoZone website, I see that they stock a few different temperatures of thermostat -- 192°F (OE temp.), 180°F (alternate temp.), and 170°F (alternate temp.). Bill says the thermostat in the engine was stock. Even before it failed, seeing the engine running at 220°F (closer to 240°F with the a/c on) made me nervous.

I'm going to swap the current thermostat for one of the "alternate temperature" thermostats. 170°F might be too low, but with no fan shroud maybe I should consider it. If a 192°F thermostat means a 220°F operating temperature, then maybe a 170°F thermostat would bring operating temperature down to 208°F. Hmm.

Edit: I looked up the PSI of the Eagle radiator cap. It's 18 PSI and not 16 PSI. That leads me to guess that the 3.0L engine ran at a slightly higher temperature than the 2.8L.

[Lwanmtr]

Wee, the adventures begin. Kinda sounds like when I tried to drive mine from DMCNW to home....cept my tempurature seemed fine...there was alot of white smoke out the back..I ended up calling AAA too, but more because it seemed the rpm's were higher than should have been at highway speeds.

Definitely flush the system if you're getting rust colored stuff out (unless its that pre-rust colored coolant).

[dn010]

Stock B280F came with a 192 degree stat and a 22lb cap! I have a 180 and 16lb cap in it now and struggle to get to the first mark (which can certainly be gauge / electronic error in my case). Maybe some of that junk breaking free from the liners is partially blocking the radiator, a flush wouldn't hurt in that case. Anyway, happy you finally got your D back.

[Farrar]

Good idea on the flush. The lowest point on the system is the lower radiator hose. My guess is I can open up the system there and at the expansion tank, and then pour water in from a garden hose until the blood runs clear. (Apologies for "Farscape" reference.)

Judging from the blowout, the current coolant boiled somewhere around 270 with a 16 PSI cap on. If I can't get the engine to run cooler, I guess I could try a higher pressure cap to raise the boiling point. But that seems like a dangerous "fix." With my luck, the higher pressure would blow the radiator - or worse, the heater core - I am not sure how much I trust any DMC parts from 1981 anymore.

My wife is hilarious. She arrived home after me yesterday carrying an AutoZone bag. "I bought something to help cheer you up!" she said. It was a can of engine degreaser.

[FABombjoy]

The thermostat will not affect your max operating temp if you're overheating. You'll still hit 250 degrees with a 170 thermostat - or with no thermostat at all - it'll just take a bit longer to overheat.

Coolant just isn't flowing, either due to pump problem or radiator blockage. No need to consider a higher pressure system as plenty of motors are making 2x power with the stock cooling circuit.

Does this car now feature a set of full-length rubber hoses? If so, monitor that the return hose isn't collapsing at higher RPM. Especially of concern since you cruise at higher RPMs in an auto -vs- manual. I know Bill loves this mod but I'd reverse it if it's been done.

[Farrar]

Does this car now feature a set of full-length rubber hoses?

It does not. Bill did engine work and anything that spiraled off of it in order to get the car back on the road. There was nothing wrong with the cooling system at the time, so he left it alone.

I will check for collapsing hoses. I will also perform a system flush and see if there are any blockages.