rdmst71

I appreciate all of your input, considering this information and from what I have learned doing a little research on line, I see no real benefits for me in changing to a synthetic oil for this engine. I would be spending more money than I need to ( engine requires 7 quarts of oil ) and I may end up creating problems that I don't have now.

Time for an oil change and I am thinking about using a synthetic oil this time and not the 5W30 or 10W40 conventional oil that I have been using in my 1948 Roadmaster. Anyone had experience using synthetic oil in a Buick straight 8 or any older engine? This engine does not have hydraulic valve lifters and the speedometer reads a little over 94000 miles. I think this is the original mileage.

Looking for cost information on factory installed options on 1948 Buick models. I have a catalog of "Engineer approved accessories for 1948 and previous models" dated September 1948, but these appear to be dealer installed accessories only. This catalog does not list extra cost items such as the black pin-striped Lavain Gray broadcloth & leather custom interior trim or the new Dynaflow Drive, available on Roadmasters only. I would like to create a window sticker with a list of standard & optional equipment for my 1948 Roadmaster - 71. I also need a copy of the connections for the rear window wiper, my car has this wiper installed but it had been disconnected and my shop manual only has the installation steps for the wiper motor and arm, not the hose connections in to the switch under the dash and out to the vacuum supply in the engine compartment.

I really appreciate all the input on what may be causing this problem, my shop manual does not always have good trouble solution information and I find that most often the best answers will come from other Buick owners who may have experienced the same problem or one close to it. This leak from the over flow pipe was being caused by problems in the heat conrtol valve or the heater core. Have not determined which one yet. After doing testing for what may be a leaking head gasket, the one recommended by Jay and a similar test described in the shop manual, I ruled out a possible head gasket leak and moved on to checking out the areas around the freeze plugs and the heater core. The temperture control knob for the heat control valve which is always turned off, was turned over to the warmest setting, but I had not noticed any heat while driving. After turning the control valve off I started the engine, let it run for about 10 minutes and there was no water leaking from the over flow pipe. I took a 20 minute drive, shut the enging off and still no water leak. I only drive this car in late spring, summer and fall and do not need or use the heater, so depending on what it takes to repair or replace the control valve and/or heater core, I may just make sure the control valve is always off or disconnect the temperture control knob, untill some time later.

I will look into this tomorrow morning. If I see bubbles, which one of the three would be the likely cause of this pressure build up?

I have coolant leaking throught the radiator over flow pipe of my 1948 Roadmaster after the engine reaches operating temperature. It's a slow leak after the engine warms up and the flow of water really increases for a couple of minutes after the engine is shut off. For years I have used straight water with a rust inhibitor, no antifreeze and no thermostat. This problem just began recently and I lose about 1 to 2 quarts of water after a 75 to 80 mile drive. Upper and lower radiator hose's seem to be in good condition, any ideas as to what I should be looking for that may be causeing this type of leak? A couple of minutes after the engine is shut off the water leak stops.

I did find this short ground cable which covers one end of a tube connected to the cylinder head and is attached to the fire wall at the other end. This ground connection is for the temperture gauge which was still working. I disconnected both ends and cleaned the connection points to be sure of a good connection. It appears that the missing ground between the frame and the body was the cause of my problems. Thanks for the response, I do welcome all of the input. I will check out anything that may have been a part of this problem Jim

Thanks for the information on the ground cable and the regulator. After taking a few days away from car repairs, this past weekend I installed a ground cable between the frame and the body, where it was supposed to have been and my lighting problems were sloved. I was not able to locate the original ground cable but since this problem just started a short time ago it must be on the car somewhere and either the connections are corroded or the cable has broken. Jim:rolleyes:

Hi Tom, Looked under the car ( front to rear ) and I can not seem to locate a strap connecting the frame and the body. Should there be some type of ground strap connecting the frame and the body? If this strap is missing where should it have been attached ? Jim

The tail lights,stop lights, Trunk light, dome light, front & rear courtesy lamps have all stop working. The first to go were the tail lights, which started to work again for a short time and then one by one the other lights failed. All bulbs are good and the head lights, parking lights, instrument panel and all other electral items are working. Today the starter would not turn over but the battery is fully charged. Per my shop manual, the tail and stop lights are not protected by a fuse and I can not locate any loose connections. Fuse's for the other lamps are located some where behind the dash panel but the shop manual does not give exact locations as to what fuse's are where. Any ideas as to what may be the cause of this and is there any way to try and slove this other than trying to use the wireing diagrams in the shop manual. :confused:

This oil filter is also available from BOB'S AUTOMOBILIA 805-434-2963. The stk# listed is OF-P112 for 1939-1947 and OF-P115 or OF-P127 for 1948 models.

My car has a manual transmission. According to the shop manual, 1948 Roadmasters manufactured late in the model year had hydraulic valve lifters if they had the Dynaflow transmission. If the valve lash has the correct adjustment of .015", after the engine warms up and with the hood closed, shouldn't the valve noise be reasonably quite even when you increase the engine speed ??

I am trying to locate a repair shop in south east Illinois or north west Indiana that can repair the engine in my 1948 Buick Roadmaster. The mechanical valve lifters are very noisy, even after engine warm up. The oil flow seems to be good and the rocker arm shaft has been replaced. Adjusting the valve lash does not help. Jim BCA # 14495