Does anyone know some Nailhead Mechanics in the Los Angeles area ? I have a '63 Riviera with a 401. Thanks So Much
Hi Kimson Your '66 Wildcat looks very nice. I recently had the 401 rebuilt and their are two major concerns: 1. Engine runs Hot in Stop & Go Traffic (210) 2. Low Oil Pressure-Max 30 lbs on Freeway. I put in a new 4 row core into the original Rad Frame. New Alum Water Pump. but the Temp slowly climbs in Traffic. Very cool on Freeway (175). I'm considering a "Pusher" Fan in the Front. And Oil Pressure is supposed to be 40 on a Nailhead. The Engine Builder doesn't think there is necessarily a problem. I've read that Cam & Main Bearing Clearance is critical on a Nailhead. But I've considered replacing the Oil Pump as a first alternative. Any Ideas ? Thank You Alan Weddle
do you have a 7 blade fan. they make a heavy duty clutch fan. both make a difference at idle for cooling. i think 30 lbs under 3000 rpm is fine, 38-40 is the most you will get with a stock pump and thats at a higer rpm. but the guys will tell you for sure when they get on.
The oil pressure in my nailhead is around 25 on startup and 32 on the freeway (2,000rpm?) If it has been all cleaned up during your rebuild and you got a fresh radiator and water pump.. Hmm.. what's the rating on the thermostat? Could you go with one that opens earlier? 210 is not a complete disaster if it stops there, or?
Your oil pressure is fine but she is running alittle on the warm side. Where is Russ Martin located out there? He is a real guru with the Nailheads. ...and Welcome :beer
Ok, first off, do you have a good fan shroud? Yes, I think the oil pump is a good place to start, along with a cleaned pick-up tube.
I recently had a 401 rebuilt and had constant hot running problems in traffic. Turned out one of the inlet gaskets was fitted wrong and it was sucking a little air on one side, lean running equalled heat. Also, in the course of tracing the problem, I fitted a flex fan and moved it closer to the radiator. The original was miles away and had no shroud. Engine runs cool all day now. :TU: Some people say you can check the inlet by spraying 'engine start' along the joins between inlet and head. Bloody hard to get under the manifold tho. I just pulled the manifold, ou: slapped myself on the forehead with a loud 'duh' and replaced the gaskets, the right way.
Were the cam bearings replaced when the engine was rebuilt???? if not , that is most likely the oil pressure problem.... with a nailhead that is using a 180 deg. thermostat , 210 deg. is somewhat warm.... the real solution is a super heavy duty rad of 4 rows of tubes with a 6 or 7 blade fan and a good fan shroud.... you may or may not use a fan clutch...or electric fans.... with a good rad and all ,,the electric fans are the best way to go.... and now days the electric fans are reliable enough...back in the day, they were considered a ''gimmick'' ....the big fan from a Ford/Lincoln 302 engine [gasp] :laugh: :laugh: work really good... and move 2500 cfm of air... which is what you need... the advantage here is that when you are sitting idleing in traffic the fan is pulling a large amount of air into the rad to cool the engine....exactly when you need it the most.... I am strongly considering installing this set up on my 425 powered 64 riv.... But,,,, if you do this,,, you will have to install a higher output alternator to keep from running the battery down while you are driving....That happened to me on my Ford truck.... :Brow: :Brow:
As far as the overheating issue: Have you confirmed the timing is set properly and the vacuum advance is working. Too little advance can cause it to run hot especially at lower RPM. Where is the inital timing set? And how many degrees advanced does it idle at when the vacuum advance is hooked up? Also, was the block was bored? If so how far did they overbore the cylinders?
Many Thanks to everyones input on my Overheating problem. I did install a Fan Shroud,7 Blade Fan,Fan Clutch and had it adjusted to open earlier, 180 Themo, New 4 Row Rad & New Water Pump.I believe Timing is 12 and when engine was rebuilt, original 401 block was bored .030 over. New Cam & Main Bearings were installed, but I'm not sure about the Valve Seats. Temp is OK for the first 45 min., but In Traffic, it just slowly keeps creeping up and I was told to turn the engine off at 210. I do know of Russ Martin in Grass Valley in Northern CA. If it doesn't improve, maybe an Elec Pusher Fan in the Front, and then install a Hi Output Alternator. And perhaps Oil Pressure is OK. Its 38 at startup, when warm, 4 or 5 at idle,22 at 30mph, and 30 on the Freeway at 65 mph. Happy Holidays to all and thanks again. Alan
Following what you say, Alan,,, then the cooling is pretty well set up... are you using the ''small'' water pump pulley that comes on the A/c cars??? if not, get one and install it and a new belt.... also go to ''direct'' vacume for the vacume advance... it makes the engine run cooler.... set the base timing at 8 to 10 deg. with the vac advance disconected.... What wt. oil are you using.... I use 20w - 40..... nothing thinner....
No on the pusher. Go to a dual puller. Alot more efficient. Check out champion radiators they have fans and shrouds cheap cheap cheap. Good stuff too. Keeps my 540 hp sbc at 160 in traffic on 90 ambient temps with a 4 row aluminum and a stock pump
210 is still within the normal range. Does it ever lose water? If so consider looking at the pressure cap.
Do a leak-down test on your cooling system... You may have head gasket or valve seat issues (if the shop installed new seats).. Ask me how I knowou: Have you re-torqued your heads since you first ran it?
To me, the fact that it runs cool at speed suggests it's either an airflow issue, or there's something that the engine doesn't like about idling for extended periods. Are you sure the fan clutch is working properly? Are the fan, shroud, and radiator all spaced correctly? If that all checks out, I'd suspect that it isn't an airflow issue. And if it isn't an airflow issue, adding an electric fan probably won't help. Another thought is that it might be running lean at idle. Also, like Doc said, make sure your running the advance off a direct vacuum source (not a ported source).
