[chiphead]

So, a new gremlin has appeared in my engine. Squirrels, namely their acorns. I was told the engine sat for some time with the intake off, before I bought the car. Didn't figure on the tree rats hoarding the winter stash in the water jackets....

Took the car for a spin this past weekend, and it started building heat on the interstate. I'm finding bits of acorn in the top tank of my radiator, and bits of shell looking stuff wedged in the tops of some of the tubes. It's a Champion aluminum radiator, so I can't have it rodded out. What now?

[b-man]

Take out the radiator.

Reverse flush it.

Turn it upside down and shake it back and forth while it’s draining.

Repeat many, many times.

A really nice workout.

Reverse flush the engine with the radiator out, after removing the thermostat.

[steve25]

That storage of food is from the little cute Chipmunk clan.

Once you have hand flushed it out and it’s all back together just fill the system with water and run the 2 part flush that DuPont makes thru the system for a while and then hope for the best.

You where not far off though, I never never knew that Chipmunks are considered a Pigmy branch of the Squirrel family.

[burd]

Take it in and have it done professionally this time

[chiphead]

So flushing really well should address the acorns. I'm guessing forward flushing (garden hose in water pump) will push the acorns up and out of the water crossover?

What about the rust? Is there something stronger than white vinegar that is compatible with an aluminum radiator? I've seen recommendations for a half cup of Cascade dishwashing detergent as a flush that's safe for aluminum.

And the acorn stuffing happened in Michigan, not sure what varmints they've got up there. Here in the Carolinas we've got squirrels, mice, rats and crystal methodists that get into cars and make a mess..

[PunchT37]

LOL

[sdbob]

Flush block also.

[77 TRASHCAN]

What Bart said!!!

[Aaron65]

Originally Posted by chiphead

And the acorn stuffing happened in Michigan, not sure what varmints they've got up there. Here in the Carolinas we've got squirrels, mice, rats and crystal methodists that get into cars and make a mess..

My '63 Riviera lived most of its life in North Carolina, but is now in Michigan. It was (and still is in some places) stuffed to the gills with little nuts of some sort. I know exactly what you're talking about!

[Greg Reid]

I have the same problem except with mice here in Georgia. I even had a mouse nest in my header's open collector once.

[chiphead]

So I pulled the radiator and flushed the heck out of it with the hose. I also removed the thermostat and forward and reverse flushed the engine with the hose. A good bit of rust mud and acorn bits came out.

I put it back together without a thermostat and filled it with straight water. It had good, rapid water flow at idle. I capped it and took it for a 4 mile cruise. After it warmed up, it ran 170-190 at 45MPH (2000 RPM) without a thermostat. Ambient temp is 82F. The engine temps seemed to level out once the electric fans came on about 180F.

How hot should an engine run with no thermostat? Electric fans come on at 180F. Dual 12" fans on a non-AC size Champion 3-core aluminum radiator.

[dataway]

Hard question to answer. Would vary based on coolant flow, radiator efficiency, condition of the inner surfaces of the coolant passages, timing, jetting and type of coolant.

If I was running typical coolant I'd be happy at 160 with no thermostat, at 82 ambient. That would show the system has some overhead. I could live with 170 too. At 180 I'd start feeling like the system might not be up to snuff in a worse ambient or load scenario. Again that would be with typical 50/50, not water.

Very complex topic. Of course as the temp of the system increases, the transfer efficiency (or at least the amount of heat removed) will usually increase too as the difference between ambient air temp and coolant increases. So I'd expect it to behave better at a higher temp controlled by the thermostat.

I would not be very happy seeing 190 with no thermostat. But then you were using straight water. Running 20-30% anti-freeze would usually help heat transfer some, but not a huge amount.

( If you are running ONLY the electric fans, then the temp setting of your fans are your "thermostat" in effect at anything below probably 30-40 mph, so the temps you are seeing would be fine I'd think )

[chiphead]

So I pulled the electric fans off and installed a '67 AC clutch fan. The clutch is a new parts store replacement. What makes sure that the clutch runs true to the water pump shaft? The clutch has some slight offset to one side, so I can see a bit of eccentricity as it runs.
Is the clutch supposed to fit snug over the water pump snout? Is it suppose to run true?

[Greg Reid]

I wouldn't use it if it's not running true. Probably ruin the wp seal in short order.
I'd put the fan mounting surface on a flat table and rotate the fan. See if it tracks true.

[dataway]

In my experience the clutch should have a recess for the WP snout that locates it properly on the WP. Usually it's a snug enough fit that there is no doubt it's doing the job. Typically requiring some wiggling to get it on or off.
Shouldn't be any eccentricity visible to the eye in either the clutch or the fan.

Is it an eccentricity perpendicular to the WP shaft? Or is it a wobble front to back at the edge.

As Greg says ... you can check the clutch, and clutch/fan combo as he described. You want no wobble, no eccentricity. If none on the table, but does have when mounted then the problem is either the snout hole in the clutch is off center (typically the bolts would not go in well if this was the case), or something is amiss with the pump snout.

[David Jones]

So weird. My son bought an early 70's Nova a few years ago and rebuilt the engine. He found a couple of acorn husks in one of the heads coolant passages.

[chiphead]

Figured it out. The 2747 clutch recess takes a brass insert that fits over the OD of the water pump snout and centers the clutch on the snout. This fan clutch was missing the insert, so it was off-center. I ordered a new clutch and it came with the insert. Mystery solved.

I ran it around today in 75 degree weather. With the clutch fan, it never got over 170 with no thermostat and no shroud. Most of the time was 150F. I'll add thermostat and shroud and report back.