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66 Pontiac Lemans issues


xxGriffonxx
03-25-2010, 12:42 AM
I just dropped in a rebuilt Pontiac 400 into my 1966 pontiac LeMans. I drove it home today about a half hour away. I noticed about halfway home that it seemed like the transmission was not catching. i lay into the gas and it revs up high but accelerates very slow. Also the starter wires were very difficult to get around the headers, i slid them through a thick piece of rubber hose and then wrapped that in a few layers of 1000 degree thermal tape. The starter wires get very hot and the battery sounded as if it were boiling on the inside. Its a 77 block with the stock 326 flywheel, torque converter, and 2 speed transmission. Could the flywheel possibly be slipping or is the transmission shot. As for the battery and wires are the wires getting hot causing the battery to boil. The alternator and wiring harness are also from the 326. Could it be overcharging the battery and causing the wires to get hot? Any opinions on the subject would be greatly appreciated.

MrPbody
03-25-2010, 09:14 AM
The battery "boiling" comes from over-charging. More than likely, the voltage regulator has stopped working properly and is "full fielding" the alternator. Using a volt meter at thebattery will tell the "tale'. If over 15 volts, it's either a bad battery or regulator.

The ST300 "feels" a little sluggish by nature. Not a good performance transmission. TH350 is a "bolt in" swap and dramatically improves overall performance.

There's a metal tube used by Pontiac to route the battery cable and solenoid wire through the exhaust. It attachs to the "studded" head bolt, 4th one back ont he driver's side. This MAY help with the hot wire condition. The later "Ram Air" cars had the tube down the BACK of the head, "curving" the wires in above the starter. Ames Performance and Performance Years both sell the part. This isolates the wires from the exhaust heat. Both also sell the heat "shield" that goes between the solenoid and the header.

Were your headers "coated"?

Jim

xxGriffonxx
03-25-2010, 04:47 PM
Well on the way back at first the 2 speed was accelerating decent. but half way back it seemed as if it was not catching. Id hit the gas and engine would rev very high but barely accelerated.. i got a th400 from an olds im gonna drop in but i dont have the money at the moment to modify the driveshaft. and the headers just have the ceramic coating they came with.

MrPbody
03-26-2010, 09:07 AM
Unfortunately, the ceramic coating doesn't offer the same protection the "thermal barrier" coating does. The "heat sink" problem has plagued GM intermediates for years.

Have you checked the fluid level in the transmission? That "sounds" like a low-fluid condition.

Jim

xxGriffonxx
03-26-2010, 03:29 PM
Yes i checked the fluid and it appears to be only a half pint low so i added a little and still the same problem. My friend told me the clutch may be glazed over or has gone bad.

jonnysocko
10-02-2010, 08:31 AM
Yes i checked the fluid and it appears to be only a half pint low so i added a little and still the same problem. My friend told me the clutch may be glazed over or has gone bad.

You said you had a 2 speed auto tranny so a clutch being shot is not your issue. Chk the vaccum line to the modulator and also chk to see if the fluid is burnt and dark looking.

Blue Bowtie
10-02-2010, 09:15 AM
Super Turbines do have a band adjustment, but read and follow label directions before being tempted to just snug it down a bit.

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