search
top

Why the CNC 1911 Isn’t Finished, or Rebuilding a DeLorean Engine.

The CNC 1911 I’ve been working on currently looks like this …

… which is pretty much how it looked four months ago. It still needs a fair bit of machining in order to get all the parts to fit. The problem is what little time I have for hobbies has been taking up by other things. First I decided to paint my basement, and before that got finished, I discovered my car had a head gasket leak.

Unfortunately, because of the type of engine, its age, and high mileage, it makes more sense to do an engine swap or full rebuild than to just replace the head gaskets. The main problem is that the engine has paper seals at the bottom of the cylinder liners, and there is a good change they will break when you remove the cylinder heads, which you may not know until you put everything back together and run the engine. If they break, to replace them, you have to pull the engine and remove the pistons. If you’re going that far you might as well do a full rebuild.

So I got a price for having it all fixed (turns out swapping in a new engine is less expensive than doing a rebuild), and it was of course, not cheap. It was in fact, most of the way toward what it would cost to have a higher performance engine installed. So I got a price for that as well. It wasn’t a whole lot more, but still more than I could spend. I would have to stick with the stock engine swap. Still, it seemed crazy to spend that much money and just end up with a stock engine again.

Then I noticed that the guy who I would have had do the high performance engine swap also sells a parts kit to convert a stock engine to the high performance configuration. The kit includes a stainless steel dual exhaust, ported heads, and performance cams, and supposedly brings the engine up from the kind of wimpy stock 130hp to 210hp. The cost of the parts kit, plus a rebuild kit, plus an engine hoist and stand comes in less than the cost of paying for a stock engine swap. So I just need to order the parts and do the work myself. Can’t be to hard right?

And so the adventure begins… Here is the car with the engine cover removed.

Now with the rear of the car removed.

All connections between the engine and car except the engine mounts removed. I also pulled the intake manifold since it was going to have to come off eventually and with it removed it’s easier to get at the heater hoses behind the engine.

With the hoist attached, ready to pull the engine.

At this point I asked Sebastian to help me pull the engine. I thought I could probably do it myself, but didn’t want to learn otherwise with the engine stuck in some precarious position and no one around to help. Turns out it was a two person job. First time we tried lifting the engine the whole car came up. The engine mounts had rusted to the engine. I had to have Sebastian slowly raise the engine while I unbolted the engine mounts from the car.

Here is the engine being lifted out of the car.

And the engine (and transmission) out of the car.

The engine separated from the transmission and mounted on an engine stand.

Valve and timing covers removed.

And one of the cylinder heads removed.

The problem now is that one of the bolts that holds the other cylinder head in place is stuck. Having a bolt break off in the block would be no fun. I’m going to let it soak in penetrating oil for a day or two and then try again.

15 Responses to “Why the CNC 1911 Isn’t Finished, or Rebuilding a DeLorean Engine.”

  1. This looks a bit more adventure than I would want to try.

  2. Especially if you aren’t bothering with the flux capacitor.

  3. John says:

    Seems fitting for the DeLorean – advanced stainless steel body powered by engine technology left over from the Chevy Vega.

    • Jason says:

      Chevy Vega? How so?

      • John says:

        The Chevy Vega engine used the same open cylinder arrangement.

        In theory the cylinder head clamped the liners in place.

        In practice, eventually the liners would begin to move against the bottom of the cylinder head leading to coolant and combustion leaks.

        Most of the time the body rusted out before the engine started having problems.

        • Jason says:

          Ah. Yeah. I think the problem is not so much with that type of design but that Chevy did it badly. With the PRV-6 in the DeLorean usually liner leaks are caused by someone removing the cylinder heads incorrectly.

          There is an advantage to the design as far as rebuilding goes. I don’t have to take the block to a machine shop to have the cylinders honed or get tools to deal with the piston rings. I just ordered preassembled piston/liner combinations that I can drop into the block.

  4. NotClauswitz says:

    A VW motor is a piece of cake by comparison, but you get what you pay for…

  5. Papa says:

    For penetrating oil – get some Kroil; kanolabs.com – also available from midwayusa.com I believe. Amazing stuff.

    • Bryan S. says:

      Or, mix up 50/50 mix of acetone and ATF… su much cheaper, and it works great.

      Rust belt + jeep x budget =/= expensive oil

  6. mike says:

    For the stuck bolt, what I used to do for stuck bolts was this: take a blowtorch, heat up the bolt, and hold a candle to it. Bam! Unstuck bolt. The wax melts its way into all the nooks and crannies, and lubricates everything like magic.

  7. Oranje Mike says:

    Hail! Hail! Hail!

    I am not worthy of any DeLorean owner. It’s a dream of mine.

  8. Sendarius says:

    If you don’t have Kroil, a 50-50 mix of acetone and ATF works well.

    But then again, maybe it’s only MY man-cave that is more likely to have acetone than a simple penetrating oil.

  9. Jason says:

    I got the stuck bolt out. I couldn’t find my bottle of Kroll, but 32 hours of soaking in PB Blaster did the trick.

Trackbacks/Pingbacks

  1. Beretta CNC Fail | Shall Not Be Questioned - [...] was experimenting with making a one-off CNC AR-15 pistol and CNC 1911 (still in progress, pending Delorean engine rebuild), …
top