Proper engine warm up temperature

[47heaven]

Just wondering what is the proper warm up temperature for the inline six engine before driving it. Lately, it's been kind of cold in the mornings here in Southern California and my P15 does not want to drive until the engine has been warmed up to about 140 degrees. Sometimes it take numerous starts before it stays running. I first tried pulling the choke out, but it seems to starve the carborator of air and it doesn't run as well as when I have the choke pushed in. I just wasn't sure if there was a "known" rule about how warm the engine should get before it driven. Anybody know?

[Brendan D25]

When you start your car I imagine you pull the choke all the way out. As soon as it starts don't push it all the way in, you gradually push it in as it warms up to avoid stalling.

[Guest Nile Limbaugh]

The procedure that's best for the car (any car) is to let it get just warm enough to pull itself and take off. The reason is that the engine will reach operating temperature faster when working than when idling. This also provides faster elimination of engine internal moisture. The faster out, the better. Letting the engine idle until it reaches running temperature does more harm than good.

[TodFitch]

Just wondering what is the proper warm up temperature for the inline six engine before driving it. Lately' date=' it's been kind of cold in the mornings here in Southern California and my P15 does not want to drive until the engine has been warmed up to about 140 degrees. Sometimes it take numerous starts before it stays running. I first tried pulling the choke out, but it seems to starve the carburetor of air and it doesn't run as well as when I have the choke pushed in. I just wasn't sure if there was a "known" rule about how warm the engine should get before it driven. Anybody know?[/quote']

As mentioned in another post below, the choke is not an on/off thing. Start with it all the way out. The engine probably won't run with it there once started, so move it in until the engine runs smoothly. As the engine warms up you will be adjusting the choke in a little at a time until it is all the way in.

That said, until I got my manifold heat riser repaired my car warmed up very slowly and required lots of fiddling with the choke -- less choke when moving, more choke when stopped and idling. A properly working manifold heat riser makes a big difference in how long it takes until you can have the choke all the way in. On my car in my local SF Bay Area winter weather it went from 5 miles/10 minutes to less than a mile and just a minute or so.

[Young Ed]

Tod Its good to hear that part about the heat riser. The spring is broken on my coupes heat riser and the trucks don't have them. I really need to get mine fixed. In the spring and fall I have major choke issues with my truck and car. Guess I need to keep practicing on the adjusting part of it.

[47heaven]

Well, I've tried to drive off without letting it warm up all the way, but it stalls on me and keeps stalling untill it's warm enough. I'm sure the heat riser must play a big part, but like other's on here, mine is broken too. In fact, I think one of the manifolds has an exhaust leak. Since I'm planning on having the manifold split, should I just have the two manifolds replaced with newer (or better) ones and then have the exhaust one split? Also, who repairs or where can a new heat riser be purchased?

[greg g]

The heat riser usually fails in the closed position (this is the position which closes the exhaust manifold and directs heat to the intake manifold chamber.

The bimatalic spring acts to open the flap against the counter weight as the temperature rises. so if you flapper is stuck it is usually stuck in the position which is beneficial to cold running, as the weight pulls it there when the spring cools. So as cars sit and quietly rust, the rust will hold the damper in the cold position in 99 % of the cases. If the flap is free, turn it counter clockwise, and clamp a vise grip on it so the vise grip are hanging vertically from the rod or weight, This will be the correct position for cold starting and warm up. thenif you want after the wrm up you can grab the hot vise grip, turn it clockwise to the other stop and hang it from a wire or something to keep the flap opened for warmed up operation

[Normspeed]

I'm running no chokes and no heat riser on mine. I warm it up for a minute or two, just so it doesn't stall during the first few blocks. Darin, for the cold season you might want to turn up the idle speed screw (not the mixture screw) on your carb just a little so it doesn't stall when cold and yet doesn't race at idle when warm.

Your manual choke has a built in fast idle linkage and cam. That may be out of adjustment or missing from your carb.

[BobT-47P15]

Well.....even changing the mixture screw might be beneficial. As far as speeding up the idle, what about the "throttle" knob, assuming it's in good working order.

[47heaven]

Well.....even changing the mixture screw might be beneficial. As far as speeding up the idle, what about the "throttle" knob, assuming it's in good working order.

Bob...I'll check into the mixture screw, but I bought new cables from Napa for the throttle and choke. I did connect the choke, but not the throttle. I read somewhere on the old site that the throttle was only used for colder climates, but it's ready to be connected whenever.

[Normspeed]

Oops, I forgot about the throttle, my 53 didn't come with one. Bob's right, cold motors do like a little richer mixture, so it might help to slightly richen the idle mixture (counterclockwise on the mixture screw). Maybe just a pinch, say 1/4 turn or 1/2 turn and see if it runs better.

[BobT-47P15]

All the throttle cable does is move the linkage to speed up the engine when you pull it out. Therefore it works in combination with the choke.....to give you less air in the carb and more engine idle speed. Also can be used as the "poor man's cruise control". (Just get going the speed you want, then keep pulling throttle out till it holds you at that speed. Works fine on level ground. If going downhill, it keeps you going even faster all the while. If going uphill, it will lug down.

[mikemaker]

When I got rid of my heat riser by way of split manifold, I noticed no difference at all. So I would tend to doubt that your heat riser is an issue. I rarely if ever use the choke. You should not have to let it warm up for long, after all, this is So Cal and it really does not get that cold. On very cold mornings, I do use the throttle for maybe 30 seconds. It should be fine. What is you idle set at? Maybe a tad on the low side.

[Eric47Dodge]

My D-24 is very cold-blooded. It will barely run until it is up to 160 or more. It has headers, so no heat riser. Have the fan off as well and a small single-core radiator from Summit, as I use it for special purposes. Have manual choke hooked to both carbs, and it won't start unless they are full choke mode. Runs rich all of the time, which is ok with me, as it has HEI and I am a little worried about burning a piston. But I have owned this car for 25 years and it has always been as cold blooded, even when bone stock.