With things starting to slow down with my work schedule, I was actually able to take this weekend off! I got to relax quite a lot, spend some time with the family, and spend a little time in the garage with the Caddy.

You may remember from my last last update about the Cadillac, that I had a few outstanding mysteries to try to resolve.

First, let’s talk about the “easy” one, the Harmonic Balancer/Dampener. You see, it seemed have been bent or damaged at some point, since one side of it was closer to the engine than the other. This created a situation where it would “wobble” on the crank as the engine was running not cool! As was preparing to remove it, I pulled some of the bolts which hold the crank pulley onto the dampener. What I noticed is that when I removed the first bolt, which happened to be in the spot on the dampener where it was “pushed out”, that the dampener seemed to start returning to it’s original shape. After completely removing the bolts, and using a pry bar the dampener was back to it’s original shape! Turns out that someone before me replaced one of the pulley bolts with a bolt that was nearly twice as long, and it was pushing on the dampener causing the problem I observed!

Now, for the more onerous “clunking” noise. When I first heard it, I thought for sure that it was an issue with the valvetrain, so sure was I in fact that I pulled the passenger side valve cover off expecting to see a bent push-rod, or a broken rocker arm, or some other catastrophic failure. Imagine my surprise when I looked under the valvecover and found no problem what-so-ever! I even pulled the drivers side, thinking I’d misjudged the origin of the noise, no luck there either. At that point I had pretty much decided that the engine was going to come out, and I needed to do a complete inspection to find the source of the issue. I put my tools away and put the project on hold for awhile.

Now, as it just so happens in the meantime I read this little gem, which described another symptom which I’d just sorta ignored. I read down to the 6th post in that thread, and I had a light bulb moment. If my valves were sticking open, it’s possible that the “clunk” I heard was the rocker arm smacking the stem of a still open valve. This would explain why it wasn’t a consistent sound which increased with RPM, since the valve(s) may not stick on ever revolution and increasing RPM probably got the valves moving enough that they did not stick. So, the valve covers came off again, and all the spark plugs came out, and I began turning the engine over by hand, fully anticipating that I’d see one or more valves on the passenger side staying open. Sadly, I was disappointed once again as everything worked exactly as it ought to.

At this point, I was again convinced that the only solution was to yank the engine entirely and do a thorough teardown and inspection. I did a quick compression test which I’d been intending to do for some time. All of the cylinders were within a few PSI of 150, except for the # 5 & 6 cylinders, which were both just north of 170PSI. That’s a fairly good sign that the shortblock is probably in decent shape, and I’ll probably be able to run this thing once I solve the mystery of the “clunk”. So I proceeded to yank the wiring, and everything else I needed to on the top of the motor, then jacked the car up and headed underneath to disconnect everything down there. Once down there, I took a quick peek to see how hard it was going to be to access the engine mount fasteners. Imagine my surprise when I realized that BOTH of the engine mount nuts were missing!

It occurred to me pretty quickly that this could just as easily be the source of my “clunk” sound, the engine slapping against the crossmember when it skips a beat. And even makes more sense that it would be the passenger side since the engine rotates in the opposite direction! At that point I put the car back on the ground, put my tools away, and called a day. Today I am going to go buy some replacement nuts for the motor mounts, and hopefully install them soon to see if that solves the “clunk” mystery. If it doesn’t this time (for sure) I’ll be pulling the motor out to tear it down and inspect it.

The next mystery for me to solve is that the spark plug in the #8 cylinder had absolutely 0 gap! I’m hoping that it was just a mistake while installing it, and not a piston which reached up and slapped it silly (that could cause a clunking noise too), we’ll see soon enough!

So when I bought the Caddy, I knew it had a cooling system issue. The previous owner had diagnosed it as a leaking water pump, so that’s where I started. Little did I know what lay in store for me!

First, the 429 Cadillac motor which is in the 67′ Deville was only made for about two years, and in very low volume. As such, there is hardly any aftermarket parts available for it. I spent about two weeks trying to track down a water pump before finally finding one on eBay. One of the biggest issues was that I could not tell if the pump was a one, or two inlet pump. None of the illustrations showed any difference between the two. I finally was able to track down a Cardone part number, and find actual photographs of the parts. Turns out I had a one inlet pump.

So secure in knowing that I’d ordered the right water pump, and a number of other supporting parts (thermostat, hoses, belts, gaskets, etc), I started tearing things down. The first thing I noticed is that the apparent leak in the cooling system probably wasn’t originating from the water pump, but looked like it was likely coming from the lower radiator hose which was bulged and clearly distressed. This is interesting, since the pump that was installed was aluminum just like the original, and could possibly be the stock water pump!

I also took this opportunity to remove some other ancillary bits which weren’t needed or functional. Someone before me had already disabled the “smog pump” system by removing the hoses from the air pump to the inlets on the exhaust manifold, but they had left the smog pump and brackets in place, so I finished the job of removing those. I also removed the A/C compressor since that system had long since lost pressure and was not operational. Interestingly, the compressor was only held on by a single bolt!!

I noticed also that the mechanical fan attached to the water pump did not have a clutch, which is normally installed on the A/C equipped cars. I decided that rather than trying to reuse that fan, I’d go ahead and install an electric fan, we’ll elaborate more on that in a later post though. The radiator also seemed fairly new. Nicely painted, no bent fins and no obvious rust inside like there obviously was in the block.

One other thing I noted was that the harmonic balancer on the crank appears damaged. It kinda looks like someone took a big hammer and hit it, causing it to bend into a sort of taco shape. Going to need to probably pull that off and see what’s what.

So, having completed the water pump R&R and getting it all back together, I started the car up to pull it into the driveway and let it warm up before topping off the cooling system. I cleaned up a bit as it idled in the driveway, then went to “tap” the throttle to bring it off of high idle. Of course, the throttle stuck! After getting the pedal to come back up, the engine was still running, and all seemed well aside from a little smoke. Then, I started to notice a “clunking” sound that was coming from the passenger side of the engine compartment. Not really consistent, and didn’t increase or decrease with engine speed. Not knowing what it was, I quickly pulled the car back into the garage, and called it quits.

And that is how it has sat for several days since then. I haven’t had a chance to look into the mystery clunking noise, and the balancer is still misshapen. I had hoped to get some miles out of the stock 429 before doing an engine swap (which was always my plan), but it’s starting to look less promising that I’ll be able to do that. A shame too since I wanted to try to get a chassis dyno run or two in order to see the “actual” stock horsepower/torque numbers of the 429.

I’ll do a bit more diagnosis of the “clunking” noise, and see if I can repair the balancer without too much cost. Stay tuned here for more!

So, one of the first purchases I made for the Cadillac was a set of new wheels. I knew the Cadillac needed tires, since the rears were showing obvious sings of dryness and cracking. I also knew I didn’t want to “waste” money on buying tires for the stock wheel size when I knew I wanted to replace the wheels. Well, the passenger rear tire gave out after less than a week parked in the cul-de-sac. I saved my pennies and ordered up the tires at the beginning of the week, and they arrived at Big Brand Tire late Thursday night.

The wheel is a Forte F36 that’s 20×8.5 with a +15mm Offset and the 5×5 bolt pattern of the caddy purchased from Gear Works on eBay. The tires are Kumho Ecsta SPT 245/40R20 front and rear, purchased from Tire Rack. I had wanted to keep the wheel size down and keep some sidewall on the tire. Lots of people are installing 22″ and 24″ wheels on these cars, and I think it’s a little excessive. In fact, even the 20″ installed leaves a little less sidewall than I’d ideally prefer, but it’s too late now!

I’ve generally had excellent service from Big Brand Tire, but they were having a rough day when they were installing my tires it seems. First, when I went to pick up the wheels with the tires mounted on them, they had neglected to gather together the Tire Rack invoice, Kumho warranty documentation, and the plastic center caps for the wheels. Then, only moments after getting them home I get a call. Turns out they’d accidentally installed the wrong tires on the car! They’d put someone elses Michelin 255/35R20’s on my wheels. I hadn’t noticed because the tread pattern and size were VERY close to the tire I had ordered, and as I said I’ve always had good service and expected that they’d done it right. Ahh well, I’ll still be using them, but it was a bit of a comedy of errors. (Mental note 255/35R20’s are a decent fit!)

Installing this wheel/tire combination was fairly difficult, especially in the rear. I had to jack the car WAY up and let the rear axle droop completely in order to slide the old wheel/tire combo out and the new ones back in. The deep wheel wells are a great design feature of the Cadillac but makes it tough to wrestle a tire up into them. The other surprise came when I was putting on the very first wheel on the rear. I put the new wheel on, and it didn’t seem to ever sit flush against the brake drum. I forged ahead with putting the nuts on the studs, hoping that the weight of the wheel was what was preventing me from pressing it up flush against the brake drum. After snugging all the lugs it didn’t seem to rock anymore, but I still wasn’t confident. It wasn’t until I got to the other side that I realized the problem. There is a small bolt that bolts into the hub through the brake drum. The back of the wheel is machined flat, where as the stock wheel has a relief in it allowing for this bolt to be installed. I simply removed this bolt on both sides. Not sure if it’s “necessary” but I doubt that the added strength of a 1/4″ bolt on a surface held together by all 5 wheel lugs is going to make a difference.

You may recall from Day 1 Triage that the brakes seem to have failed on the Caddy. So while installing the wheels and tires, I also attempted to bleed the brake system. This too, was a bit of a comedy of errors. I have the correct tools for loosening the bleed screws, however even these don’t have the clearance necessary to really get a good “bite” on them. I managed to open them up, and do some bleeding, but my bleeding tool also wasn’t great. If anything I think I may have introduced more air into the system. I’ll have to re-try again later, probably with a custom built tool to loosen the bleed screws and a better bleeding tool.

After bleeding the brakes, and getting the new wheel/tire combo on I wanted to see if I had any brake left at all. I was convinced that the brake system had a serious failure because the cadillac has an automatic system for releasing the emergency/parking brake when the car is put into gear. This mechanism depends upon the brake being depressed, and uses a pressure sensor in the system to determine if it is “safe” to release the parking brake. After the car was delivered, the parking brake was never released when the car was put into gear. After my botched bleeding attempt, there was some trepidation, but I manually released the parking brake with a small lever under the dash. The brakes held! I then took it for a brief victory drive.

Of course, to get the car started in the first place, I had to grab the battery from the X. Seems there is a draw in the caddy which slowly drains the battery when it is not driven. Worse still, in swapping the battery in, I noticed that the positive (+) cable is routed through the radiator support, and is likely to get worn through and short to ground. Going to have to re-route that post haste! Mark up two more things for the todo list.

The drive was good, it is missing a bit at full throttle. Also when you floor it there is a hesitation before the engine responds. Some carburetor and timing attention is in order. Taking it out for a spin also reminded me that I still need to replace the water pump and get the cooling system working. But, progress none-the-less!

Ohh and, if there was any doubt that this is a big car, here’s the proof. 4 fullsize tires in the trunk!