Well there she is, the source of my clunk! And, the way it’s sitting in there explains why the engine wouldn’t turn past TDC as well since that thing woulda been right in the way. So far as I can tell it’s a small(ish) washer that got folded in half. You can see a few more shots of it over in my Flickr set. What remains a bit of a mystery is how it got there. I’m guessing it entered through the intake, and it’s possible it was sitting on top of the throttle blades of the carb. Tough to say if it was there when I got it, or if I managed to drop it there while I was working.
All in all, there doesn’t seem to be much (maybe any?) damage from the whole debacle. The you can see both the cylinder wall and the combustion chamber for that cylinder, and they both appear unharmed!
Remember back when I described that one of the cylinders had a spark plug that had 0 gap and appeared damaged? Yup, you guessed it, that plug came from this cylinder. Makes sense, all of the steel for the cylinder wall, piston, and head are harder than the washer would have been, and the spark plug would have been a softer metal as well. Soft enough to sustain some damage from that thing flinging around in the cylinder. This also explains why it seemed fairly inconsistent, when that cylinder was not on it’s power stroke the washer would have happily just moved up and down the cylinder wall in place. Then when there was ignition in that cylinder, the pressure probably sent it flying around!
I also made another discovery while I was working. The bolt on the front of the crank that I’d been using to turn the motor over, doesn’t actually belong there! The balancer is simply pressed onto the crank with no big bolt to hold it on like you find on many other motors. It’s becoming more and more apparent to me that one or more people who’ve worked on this thing haven’t been terribly methodical, and clearly didn’t have a service manual to reference. In spite of that, the motor appears to be fairly low mileage and it quite good condition.
The plan now is to do some more inspection and measure things to see if they match the tolerances set out in the service manual. If everything checks out, I think I may just put her all back together and run her. Going to keep my fingers crossed that everything is as tight as it appears to be so I can get some miles outta this thing!
#1 by Mike on February 4, 2010 - 10:01 am
Are you sure this is a 429? On my 67 deVille, there isn’t a smog pump, but lots of folks like to swap out the 429 for a 472/500 from the 70′s because you can get parts for them.
#2 by RyanG on February 5, 2010 - 11:48 am
Hey Mike,
Eagle eyes! You must have seen the smog equipment in one of the photos since I don’t recall mentioning it!
Yes, I am quite sure it’s a 429 there are a few obvious signs.
The exhaust manifold only has 3 runners, the center two cylinders on either bank share a runner. On the 472/500 it’s the more traditional head setup with 4 exhaust runners per cylinder bank.
There is a crossover pipe for coolant that goes between the heads, and into the top of the water pump, this was a design unique to the Caddy 429.
The 472/500 firing order is 1-5-6-3-4-2-7-8 and the 429 is 1-8-7-2-6-5-4-3. I had some ignition trouble and verified that my motor uses the 429 firing order.
My service manual tells me that only cars which were built to be registered and driven in California would have had the smog A.I.R pump, so there are probably more cars without it than with it. This does tell me that my car is an original Cali. car though.
#3 by Mike on February 7, 2010 - 9:34 am
Looks like it might be time for a rebuild! I bet that washer came of the air cleaner when someone was being careless.
Question for you: I’m looking at buying rims for mine. Did the rims you bought have any clearance issues? I’m nervous about ordering something that won’t clear the fender skirts.
#4 by RyanG on February 9, 2010 - 12:08 pm
Hey Mike, nope these wheels fit perfectly! They’re a 20 x 8.5 with a +15mm offset. You can read more about them and the tire I put on it in my other post.
As for this motor, as far as I can tell the washer didn’t do any appreciable damage. In fact, other cylinders which didn’t have a washer in them have more score marks! I intend to just put it back together with a new gasket set and some cleaning, and run it!
#5 by Dave on March 7, 2010 - 8:30 pm
We’ve just done the heads on a 67 caddy that hasn’t run in 4 years.
We’re trying to get it going now and are only getting a weak yellow spark. It wants to go but can’t quite get there. Any suggestions??
Can you confirm the location of the number one cylinder? It has the 429.
thanks, and good luck with yours.
#6 by RyanG on March 7, 2010 - 11:15 pm
Dave, Cylinder 1 is the drivers side front cylinder. Odd cylinders on the drivers side, even on the passengers, firing order is above.
I had to replace my coil when troubleshooting other issues, but my spark is nice and hot white.
Hope you get yours figured out, I’m still working out a few details before mine runs again!
#7 by Dave on March 8, 2010 - 7:39 am
We had it right. We’re doing the car while on vacation in Mexico, so parts are hard to come by.
Hope to have it running soon