So we took the 49 on it's first extended milage drive today. Up until this time we had taken it for short drives lasting at most 1/2 hour. Todays drive was 45 miles at speed limits and some tollway miles. The oil pressure runs about 40 lbs and the temps run just under 200. It's a 235 bored 60 over with dual carbs and Fentons. The standard 3 speed with a 54 powerglide rear. It ran anywhere from 45 mph to 70 mph just fine on the first part of the drive. Everything was going fine until about 30 minutes into the drive. Then it was if someone put out the anchor...the engine dropped in rpm, the temp rose about 15-20 degrees, the oil pressure dropped a few lbs and it just seemed sluggish. We got to our destination and the temp seemed to go back down by the time we drove into the parking area. The coolant was in the overflow tank but none had blown out. And it was not boiling over. So after 5 hrs we started home. Same thing happened although this time the end of the drive was in the city so about 5 blocks from home the engine was laboring and the temp was going higher so I pulled over. At that point the radiator started blowing by the 4lb cap. So we waited a little and filled it back up to make it the rest of the way home. It started up but after about a block it was laboring again. I went the 5 blocks home and by the time I got home it was again boiling over and the engine was laboring and I had to keep feathering the throttle to keep it running. After sitting about 4 hrs I started it up to pull it into the driveway. It started with little cranking as usual. The temp gauge was down but by the time I had backed it up and pulled it into the drive the temp was creeping up towards 200 again. It had absolutely no power to back up a slight incline and the engine seemed under a load-its bogging almost like I am starting in a high gear but it is just idling. Fan, water pump, alternator is turning fine. Seems to be firing on all 6. The idle is way low from what it is usually. So what is going on?
This is a crazy, possibly dumb question, but i'll throw it out there anyway...Is it possible that you had a brake hanging up, adjusted too tight OR do you have the fluid topped all the way with no space in the master? I had a similar problem with my 53 last year headed to a show that was about an hour and a half away. About 40 minutes into it, it started to slow down and act as if it was losing power. A few day's before the trip i topped off the master cylinder, and believe it or not, i filled it too much and there was no place for the fluid to go as everything heated up.. No problems prior to that, ever.. Removed a little fluid so there was about 1/4-3/8 distance between the fluid and top of the master....No more problems. I'm running stock brakes all around with the single master... My car DID start to heat up as well, and it only happened after you drove for a while..I did smell the brake odor though once i started poking around on the side of the road..that's why i started looking there first instead of under the hood. Again, just brainstorming.. best of luck. Tony edit:...well, my problem was brakes...but the lack of power and low idle after it's been sitting that long dosn't sound good....like it's 'tight'. It may be lower end related....i missed that the first time i read it..sorry about that.
Not things you'd like to here,but it could have a spunbearing and or a blowen head gastket or a crack. 4lb. cap is maybe stock,but still very low[I'd run at lest 7lb. Check stuff out well. Hope some one got some better A to Q.
Could you been starving for fuel. Getting lean and the temp going up. I like the brake idea best however.
Sounds like a Stovebolt doing what Stovebolts do. Lucky it didn't go BANG! There's a reason so many people put other engines in those cars!!
With two(?) carbs your distributor's vacuum (and mechanical) advance doesn't work the same as with one carb. How do you have it hooked up? Running retarded (or way too advanced) will make it get hot and lose power.
I lean toward blown head gasket, that after awhile led to coolant being mixed in with oil and wearing down the rod bearings and whatever else that got lubrication. It would help to have some more history about the engine, if it is rebuilt, what year engine is it, etc. I recall getting a 235 short block and finding out I needed some weird head bolt to get oil to the rocker arm ***embly. Need to know more about the engine to make a better opinion of what happened. The brake idea is a good one, but I think you would've noticed that the car slowed down by itself if the brakes were dragging.
Very possible it could be something electrical? I have the same motor and it did something similar. One day on my way home from work 30 mins away, it started loosing power, jumping around, backfiring, and just running really rough...turned out it was all electrical. Should be an easy fix since there's not much too it at all.
Pull your plugs and see what they tell you. What's your oil look like? Any residue at the tail pipe? The advance question is a good one. Flatman
What's wrong with my inline six? Is missng two cylinders. Seriously I had similar issues (didn't heat up though) with my flathead, and it was a vacuum advance problem.
Might check your timing and the vacuum advance to see if they are set correctly and the vacuum advance is working. It can overheat if the timing is too far off in either direction.
check the oil for coolant, and the coolant for any combustion g***es. if you find those to be ok..that may rule out blown head gasket..(blown gasket could cause over pressure of coolant system, and loss of power due to the cyl. trying to burn the fuel/coolant mixture..any white smoke?) move on to the ignition system..(advance via. vacuum..or lack there of. although i would think it would be too much advancement for these symptoms?)..the draging brake syndrome..mmm guess its possible..check that too.
Some things to consider if you still haven't gotten to the bottom of it - Verify that it's getting enough fuel, too. Normally a clog in the fuel filter or line just causes the motor to bog and not have power, but with the 4-lb cap I can see where the resulting lean condition under power might cause you to get hot enough to boil over. I would also make sure the water pump is circulating the coolant while I was checking things. I don't know how you have your 235 set up in the car but some guys run shortened water pumps to make them fit, and there's always the off chance you get one the impeller spins on the shaft instead of pushing coolant. Seems to me from past posts this motor is a fresh build, but I guess it's not unusual for these to have head gasket issues - a compression check might be an easy way to check for signs of trouble there without tearing the motor down.
It's a freshly rebuilt motor. If it was the water pump, wouldn't it have run hot from the beginning, not suddenly after 45 minutes of driving? I think the 4lb cap is too low. I think you're supposed to have a 7. Also check your thermostat. My 59 was running hot recently. Bad thermo even though it was only a year old. My wife had the same set up as USmile on her 51 and she had no problems with getting vacuum to the vac advance... but the unit could be bad. Could the distributor come loose and rotated? I like the brake theory, too. Easy to fix, too!
So, it was fine when stone cold, but after a period of time it started acting up, and you were able to make it do the same thing a second time, correct? If it was stone cold when you left to go home, and it was fine until you were nearly home again, I would think that the problem is time/temp sensitive?? At this point I would say weak coil or condenser, or a bad batch of gas (vapor locking). I just had the bad gas problem hit me in Davenport Iowa last weekend. What are you using for a distributor, and is it points or electronic? Was it pinging or making any other sounds? popping, surging, backfiring? A compression test will tell you if the head gasket is bad. If the brakes were dragging, you should've smelled it. The specs for setting the timing are for with the vac advance disconnected. Fresh engines tend to run hot for many miles until they break in. Can't say at this point if the temp and running condition are totally related... What are you using for a thermostat? Does the lower radiator hose have a coil spring in it to prevent collapsing?
That is the ****ing dumbest thing I have heard anyone say in quite a while. If I missed the sarcasam then I'm sorry. People rib me all the time for being an Inline fan. I'f not... The above statement stands.
First of all thanks for all of the suggestions. Let me answer a few of the questions in hopes that it will help locate the problem. Engine is freshly rebuilt 235 bored 60 over with a mild cam, dual 2bbl Carter Webers on an offy intake with hot water heat, Fenton headers, HEI all from Tom Langdon. The initial timing was set to 18 BTDC as per Tom. The engine was fired up and ran fine and the cam was broken in for 30 min @ 200-2500 RPM. It got a little hot but with a big *** fan we put on it did fine. The radiator was cleaned and tested, all new hoses, coolant looks clear, running a 180 degree thermostat, short water pump. It has run like a champ on short runs...lots of pep, rap good through the dual exhausts and always run just under 200 on the temp gauge which I had tested using a pot of boiling water and a couple of accurate thermometers to get the true reading on the gauge. New Fuel tank that is vented new fuel lines, new fuel pump...we've run two tanks through it. On this recent trip we ran one tank down, stopped and filled up so it had 2 different brands from two different stations. From cold start to the first hint of something not right took about 30 min both ways. The first I was cruising at 65 on an open tollroad - 200 temp, 40 lbs oil, rpm about 2800. I had just come out of construction zone or 45 mph and picked it up to 65 when it felt like I hit a stiff head wind, the rpm dropped a little, temp climbed 25-30 degrees and it just sounded like the engine was under a load. I backed it down to about 55 and it stayed like that until we reached the end of the ride. Coolant was hot but not boiling over. After sitting for over 4 hours, it started right up and we headed home. Took a different route home...back roads with some stop signs, it ran through the gears fine and temps held at 200, rpm sounded fine. Stopped for gas. Started back out temps still at 200 ran fine. About 5 min later got on the expressway for the last 10-12 miles. Was in the same 45 mph zone but moved constant. Outside of the zone it opened up to 55. About 2 miles from home it acted just like before. Only this time it was city driving not croweded but lower speed and some stop lights. Eventually it just bogged down and I pulled it over and then it started boiling over. After sitting about 3 hrs I started it up to pull it in the garage and it ran like ****. Tried getting it started today...it ran like ****. Idle speed won't even hold I have to keep giving it gas. It sure sounds like timing to me also. I took out the plugs and they all look fine. The mystery to me is that it has been running fine with no timing issues until this longer drive. Checked the oil and the dipstick is clean with oil at same level as always. Coolant looks clean. There was no smoke and there was never a smell of burning brakes. I did check the dual master today and it was pretty full so I took osme out, but the engine is still running poor. Now some questions that may seem obvious but it's been so long since I had a vehicle that I could actually work on that I have forgotten much of what little I knew. Why would it run fine for about 30 min and then change so abruptly to loss of power, increased temp, etc? The distributer is installed so the vacuum pot is super close to the engine block. Can that be removed and turned so the pot is away from the engine more? I'm running dual carbs but the vacuum hose is only connected to one of them...do I need to attach it to both of them some how? How do I check that the vacuum advance is actually working? If the vacuum advance was not working properly, would that account for it running like a champ for 30 min and then suddenly going south? Again, thanks for all the help.
First I would run a compression test as a couple of the others suggested and elmiminate the concept of having lost compression. You say the tank is vented. Is it vented through a canister (filter) or does it have a vented cap? If it has a vented cap make sure that the cap is actually vented.
You can turn the vacuum pot away from the engine block if you want, provided you have room for it pointing somewhere else, and that your vacuum hose/line will accomodate it. You'll have to move the distributor gear over one tooth when you do it. Check the timing advance with the vacuum connected, and then with the vacuum disconnected. If it is advanced more with vacuum connected, then your vacuum advance is working.
Glad to hear that you've got the '49 out on the road. How'd that differential work out for you? Something that I thought of as I was reading through this... Did you put in a poly fuel tank? If so, check your fuel filter for little black curly cues. (Yes, there is a story behind it.) I've also encountered the brake drag problem. With mine, I had the wrong spring installed on the pedal, and it would let the pedal fall slightly letting the brakes drag. Can't say for sure what the answer is, but I'll almost bet it's something stupid simple. Don't overlook the obvious. Phil
sounds to me like a thermostat issue. maybe the engine is getting hot enough to cause vapor lock, which would explaine the sluggishness of the engine. maybe you're temp gauge is not reading correctly (is it electric or mechanical?)
Wrenchbender...diff is working fine...before the problems it was flaying on the toll way at 70+ mph at less that 3000 rpm. It just purrs at 60-65. If it was a blown head gasket, would it run fine for half the trip and then act up but then after it sits be fine again? The temp gauge was checked using a pan of boiling water and two accurate thermometers so I know it is reading as it should...it is electric.
If it wont idle it sounds like a va***n problem,you might want to see if the carbs and manifold are tight. Who supplied the shortened pump as there are two types being sold,one has the 216 size pulley and the other has the normal 55 to 62 235 size pulley. If you have the one that has the 216 size pulley it could be spining the pump too much,I have heard on a chevy truck forum that the 55 to 62 style pump needs a pulley about the same size as the crank pulley to work the best and some had problems with the pump with the small pulley. When I put my 37 togather I used the pump with the small pulley but did not have any problems even with 4.10 gears but I had a 4 row radiator but when running it hard on hot days I heard some gurgling from the motor after it was shut off,I did not have a working temp gauge at the time and the pump went bad and into the radiator so I bought a adpater that mounts a 54 on back water pump to the 55-62 motor and now I can use a regular fan. Jeff
It sounds like a vacuum leak (as you say it idles poorly now). As mentioned previously check to make sure the intake (and both carbs) are tight. Failing that, your vacuum advance diaphram could have ruptured, that would give erratic performance if it didn't fail all at once, to crummy performance (as you currently describe) if it has completely failed. The old test for a vacuum advance can was to blow cigarrete smoke into the vacuum can, w/ a hose (and the cap off the dist) if you saw smoke coming out the back of the can (on the inside of the dist) you knew it was bad. If you have a vacuum pump (mightyvac?) you could see if it holds a vacuum (if you don't smoke), as some of those advance cans need alot of vacuum to do anything. It could be a blown head gasket, now, but I would expect with your description that isn't the cause (if it is bad) rather it would be a symptom. A compression test is the best idea there. If you were getting advance from the vacuum port you have it hooked to now, it doesn't need to change. If you were getting oil to the top end before, and the pressure is still the same, I don't see where that would be part of the problem. Good luck. Oh, just out of academic curiosity, is this the 53 splash oil engine or is it full pressure (has nothing to do with the current problem, just curious and can't seem to find it in the search)? How do you like the progressive Carter Webbers (up to now)?
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