66 Valiant

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Sep 25, 2008
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Location
central ga
A few weeks ago I picked up A 1966 Plymouth Valiant 100 2 door. The car is in so-so shape. 170cid/2.8l slant six,1 barrel carb and the modern anti theft device--3 speed on the column manual transmission.The car cranks,runs and moves and stops. Visually the car is pretty ugly.It seems to have been the goldish color that was popular back then. Now it is multicolor -gold roof unevenly applied dark red/burgundy type paint over what appears to be the original paint and a blue replacement fender(it appears to have been in a minor fender bender in the distant past.).The gold is badly worn ,,the red has faded and worn away leaving a splotchy appearance that has the white (primer maybe?) and blue and bare metal in some places showing and red overspray on emblems and grille. The interior needs door panels ,headliner, carpet ,seats basically the entire interior needs replaced/redone.The interior was tan and beige. However the body is almost rust free ,a small 8in x 3in patch behind the passenger rear wheel well.
Mechanically ,as I said it cranks and runs. It does not smoke even after sitting up for a week.The fuel pump and alternator and oil and filter appear newish.At some time in the past the ignition switch went out and someone installed a pushbutton starter. The brakes are surprisingly good. The transmission shifts well(the chrysler shift pattern is very tight in comparison to the Ford 3 on the tree I've had.You can actually start off in 2nd and 3rd gear from a stop.The lighting is a mixed bag some work and some don't haven't delved into that yet.The only issue mechanically I've found is that after about 10 minutes it starts to run hot. The fluid in the system was brownish. I pulled the thermostat housing and there was no thermostat.I thought maybe the rad was filled with sediment and drained everything and refilled. It still ran hot. So I pulled the radiator and the water pump on the chance that the vanes on the pump were gone. Here is where it got interesting ,the water pump housing still had remnants of the factory Chrysler Red paint. The odometer shows 57 k and I thought yeah right, but if the factory paint is still on it...I wonder how long this car has sat up. Well any way the pump was in good shape. I have not reassembled the system yet.
The most recent p.o. was a retired mechanic who passed away after a stroke while fishing.He passed away in 2019 and the car was last tagged in 2017.His widow is now parting with some of his project cars. I may have paid a little too much but I wasn't going to beat up an old lady too much. I think I can handle most of the cars issues myself. The objective is a decent driver not a show car.
I'll be probably post some updates as this goes.
 
I like the look of the mid 60's compacts. Chevy 2, Ford Falcon, and Valiant. The Dodge Dart has a very unique look to it that's not all bad. These are interesting cars and overlooked in my opinion.

Congrats on your purchase.
 
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Having the radiator “boiled out” along with adding a thermostat may cure the problem. If you can find a frost plug that’s easily accessible you could knock it out and run a garden hose in the thermostat housing and flush the crude out of the head and block. Could be a lot of rust residing in and around the cylinders-water jackets. Retarded timing can also cause an engine to build heat. Set the points first and then timing next. If it it has “live” vacuum to the distributor advance, set the timing with the advance disconnected. Just thoughts at random.
 
Hard to say, don’t think the mechanic did it, but I want to say, “many” pull the thermostat when they have overheating issues, thinking it’s the culprit. My guess, it’s been used for years with plain water and needs a good flush. Radiator may well be packed full of junk, I’d look into it, not sure what it’d take to get a good replacement. I don’t think these cars used a radiator shroud? sometimes those get pulled, but can be pretty important.

Sounds like it’s got some deep gearing, if you can take off in 2nd. A 170 though isn’t a powerhouse so it may need to spin high if you have plans for highway driving—not sure if a rear gear swap makes sense (and is likely way ahead of where you are right now).
 
Not many today can drive a manual much less a 3 on the tree
I always wanted one. Just seemed cool to me. I suspect today though I’d hate it, 3 just ain’t enough, unless if I’m just putting around town, and even then.

I’ve heard of swapping in 4 speeds, and rigging up something like a parking brake lever to work the reverse lever on the transmission. Not as cool though, and would making rocking a vehicle that much harder to do.

Now the ones with overdrive must have been interesting—a planetary on the output shaft. I think many would freewheel during coasting? which I’d hate, but could be a nice addition, especially if one wanted to bring the rev’s down on the highway.

Been a while since I had a manual, much less driven one with a Z bar to work the clutch—my recollection was, the imports, with either cable actuated or hydraulic clutch, were nicer on the knee, and smoother too.
 
Please keep us updated. I still miss the 225 slant-six Duster I got rid of 25 years ago. Mine had 3 on the floor, but the weathered paint and melted rear speaker grilles were my theft-deterrent strategy.

A couple comments above said what I was going to suggest--flush the system, put in a thermostat, check the timing and vacuum advance, and then check the radiator core for blocked tubes if it still overheats. It seems like somebody might have pulled the thermostat trying to fix an overheating problem.

I had to use my Duster's heater as an "auxiliary radiator" once, in a city traffic jam. The radiator was seeping in multiple places by then, so I replaced it soon after and never had any more overheating problems. Actually, it struggled to get warm in Midwestern winters without a pizza box in front of the radiator.

I had no shroud and a fixed fan, 4 blades if I remember correctly. If yours has the same setup, I wonder what difference a shroud and a clutch fan could make for cooling, power, and MPG.

By the way: I don't know if you have ever worked on one of these, but don't drop any screws into the distributor while changing the points and condenser. And if you do, get them out before turning the engine over. I'm not sure about a '66, but mine had a plastic dist. gear that broke when a screw fell down inside.
 
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I had no shroud and a fixed fan, 4 blades if I remember correctly. If yours has the same setup, I wonder what difference a shroud and a clutch fan could make for cooling, power, and MPG.
More work but I wonder if an electric fan conversion might work on all fronts—I can’t imagine a slant needing that much cooling? Kinda goes against the simplicity of that car, though, might need more alternator too, and Mopar liked to use ammeters. IIRC that was a weak spot, and some would put big diodes across them, to prevent burning out the gauge (me, I’d probably bypass and install a voltmeter).
 
I'm changing the subject...a little bit, but about 25 years ago, my mom bought a mid-60s Dodge pickup with a slant 6/four speed on a farm sale auction. She paid $500 for the truck. As she was paying for it, two auctioneer helpers came out of the barn with the tail gate that had been found up in the hayloft and said that it obviously goes with the pickup. The original owner purchased the truck new, took the tail gate off and put it up in the hay loft and never used it. It had absolutely no dents and was just a little faded on the paint. Mom used the truck for a good 15 years around her house and never put the tail gate on it then either.
About 10 years ago, she wanted the truck sold, so I put an ad on Craigslist for it. I got $750 for for the whole truck. The buyers wanted to get it cheaper, but I told them the tail gate alone was easily worth the selling price. Mom was happy because she told everyone that she actually made $250 on that truck.
Anyway, at least by reputation, the engine in your Valiant is a good one.
 
I always wanted one. Just seemed cool to me. I suspect today though I’d hate it, 3 just ain’t enough, unless if I’m just putting around town, and even then.

I’ve heard of swapping in 4 speeds, and rigging up something like a parking brake lever to work the reverse lever on the transmission. Not as cool though, and would making rocking a vehicle that much harder to do.

Now the ones with overdrive must have been interesting—a planetary on the output shaft. I think many would freewheel during coasting? which I’d hate, but could be a nice addition, especially if one wanted to bring the rev’s down on the highway.

Been a while since I had a manual, much less driven one with a Z bar to work the clutch—my recollection was, the imports, with either cable actuated or hydraulic clutch, were nicer on the knee, and smoother too.
My 69 Chevelle was a 3 on the tree. I really liked it. My friends talked me into cutting a hole in the floor and mounting a floor shifter. Never really liked that.
 
Regarding the running hot... Assuming the radiator and water pump are working properly, there is a basic test for 60's vehicles. If it runs hot around town, suspect airflow across the radiator. If it tends to run hot at freeway speeds, consider coolant flow as there should be plenty of air across the radiator, or radiator efficiency (too small).

Good luck and sounds like a fun project.
 
My first car was a 1966 Plymouth Valiant 4door with a three speed manual. It was basic transportation. The shift linkage messed up and was repaired with a set of vise grip pliers. When I got rid of the car, the vise grips went with it. This is what mine looked like.
 

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A car that old might have used just water for cooling or the old style antifreeze. The suggestion of getting the radiator boiled out is a good one. It might be all sludged up.
 
A pal had a first year Plymouth Valiant Barracuda.
Many (all?) of the front end sheet metal parts (headlight bezels, grille) were the same.
That back window put the words, "glass coverage" into our vocabularies.
No 20" wheels needed.
 
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