vapor lock problem

[61econoline]

ok here goes.

IT's a 61 econoline with a 200 ci from a 70 maverick (at least that's what I was told). The air cleaner has a maverick sticker on it with the 125 hp sticker also. I since have taken the sticker s off and painted the air cleaner. I scarfed a duraspark II system form a 70's ford in a junk yard and it plugged right in. I swapped the generator for an alternator. new fuel pump etc.

My question is all of the sudden I am having vapor lock problems, never had them before with the van. The las thing I did before this started happening was to replace a freeze plug on the back of the block (behind the flywheel). There are two of them and I replaced the upper one.
There was all sorts of sludge around the plug hole when I pulled the old one out so with finger I managed to get most of it cleaned out. When I installed the new plug I thought maybe I pushed it in too far but it didn't leak and looked like a good fix. I drove the van to work and back (26 miles total) for a few weeks, everything was fine. Now the temps outside are around 100 and the thing vapor locks. The temp gauge (stock) reads higher than it did after fixing the freeze plug ( now that it can hold pressure) but it did run cooler then. Had to add about a gallon of water every other day.
When it first happend I thought it was an electronic problem because the engine just died, no warning no sputtering just quit. So I bought a new coil rotor and cap. didn't help. So I bought a new ignition module, didn't help.
My thought is that if I put that freeze plug in too far it may be causing a restriction and maybe some residue built up around the plug and it's running hotter now.

I hope this is enough info for you guys to get your heads wrapped around it. Thanks.

 

[early ford fan]

could it be that the sludge you knocked lose clogged the radiater?id flush the cooling system and change the thermostat.

 

[ludwig]

You may have gunk in the tank plugging the inlet. If it works fine after standing a while then dies while running and then starts up again a bit later, the debris in the tank are blocking the inlet filter and then falling off when the suction stops.

 

[gtm1086]

Vapor locking seems to be one of the biggest issues discussed here over the years. If you are running the stock carburetor that still has the water plate on it you may want to bypass the flow of water through the plate. Next clean out and flush your cooling system. If the radiator hoses are more than a few years old I would replace them and while you are at it install a 160 degree thermostat and a 16 psi radiator cap. Next bump your timing up to at least 10 degrees. Retarded timing can cause hot running. another thing to look at is a restricted or plugged exhaust. I feel one of the best things I did to help resolve vapor locking was install the 2 barrel Holley carburetor. I feel that the stock one barrel is prone to boiling the fuel out of the float bowl

Any way just my two cents worth

Gary

 

[kukm66]

there is an old trick for a temporary fix on vapor lock and that is to place a series of wooden clothes pins on the line. They act as fins to disperse the heat.

 

[Asa]

The temp gauge (stock) reads higher than it did after fixing the freeze plug ( now that it can hold pressure) but it did run cooler then. Had to add about a gallon of water every other day.

the guage will read hotter because by containing the pressure in the system, you've raised the boiling point
unless it's getting into the range where it's obviously boiling over, don't worry about that part

do you have the heating/de-icing plate for the carb still in place? it's a spacer that goes between the carb and the head, and the coolant runs through it, a fair amount of previous problems of vaporlock have been solved by re-installing that

 

[61econoline]

Thanks for the input let me see if I can cover the replies.

No there was no coolant/heater spacer on the engine when I got it. I had a 63 falcon at one time (gave it to my son). It had one so I know what they look like.

I replaced the exhaust with 1 3/4 steel tubing and a home made muffler. The pipe that was on there when I got it was 1 3/4 figured I would stick with what was working. I did make a muffler with a 1 3/4 inlet and 1/3/4 oulet encased in a 4 inch steel tube about 2 feet long The tubing crosses in the center of the 4 inch tubing (i welded it together to keep in place) sounds more like a quiet tractor now. We have a bender at work since we do metal fabrication. Even had the flaring tool for fords. It could be restrictive I don't know for sure.

When it stalled the last time it backfired terribly. I took the air cleaner off right away (very hot) and could see the fuel boiling in the carb. I still had gas coming to the carb but it took awhile to stay liquid before I could start it again.

The radiator hoses are rather old and a little swollen will replace those along with a lower temp thermostat and 16 psi cap. I had the radiator apart when I first got it and had to use a coat hanger on a drill to clean out the tubes worked great and ran cool after that. The water pump is also new. Has anyone heard of using white vinegar to flush the cooling system? Works great on coffee pots.

I re-routed the fuel line to run around the valve cover hoping that would help. Looks nice but had little effect.
I'll let you know how it goes when I've made the changes Thanks much.

 

[Asa]

i'd try and find one of those spacers and see what that does

if the radiator is getting blocked, it should have hot and/or cold spots on it, might be worth checking

 

[fordconvert]

Have you been through more than one tank of fuel since this problem started? You could just have a bad tank of fuel. Did you get the problem tank from a different place than you usually get fuel for your older engines? You could have got some fuel with ethanol. Its getting prettty common all over the USA now. Even 10% ethanol lowers the boiling point of the fuel, more even lower. Even if they claim its only 10% it does not tend to stay mixed well so anything possible. I have read about cases where there ended up being as high as 30% because of poor handling and storage techniques. You then add in the moisture that it tends to suck in and your engine is not happy. We have had ethanol in my area since the early 90's so its old news to me but some areas are just getting it so I figured it was worth a mention.

 

[sixpony]

I think this is one of the inherent flaws in these old sixes, having the intake and carb directly over the exhaust manifold, my ol mustang is a hard starter on hot days when I shut it down for a few and the carb soaks up the manifold heat (notice how the temp rises after shutdown?) then she runs fine after the coolant flows for a while. Opinions vary on the reason for the coolant plate, in my humble opinion though its there for cooling purposes, coolant is definitely cooler than exhaust manifold temps, and if I'm not mistaken your engine sits in a box between the seats, that can't help the situation. And as fordconvert said the ethanol don't help either.

 

[ludwig]

Other guys with Econolines here also have problems with higher temps in the doghouse with its limited airflow. The stock coolant flow spacer plate not only heats the carb when it is cold, it keeps the mechanism at a constant operating temperature when it is hot. To be sure, it is a higher temp, but it is a constant temp that will limit over heating.

 

[61econoline]

Well I don't/won't buy ethanol I think it's a waste of valuable resources so that's not the problem but thanks for bringing it up.

I am painfully aware of the doghouse heat retaining issue but I love this van. I'm pondering ways to keep the doghouse cooler maybe an electric fan that kicks on at a certain temp and keeps the air flowing when you slow down. I've also considered running a vent from before the radiator directly back to the exhaust intake manifold.

Another factor that might have an effect is that when the previous owner installed the 200 in the van he had to cut away part of the air cleaner where the doghouse lid support is so it would fit which makes it draw all that hot air from above the exhaust manifold. So I think moving that support arm for the lid and turning the air cleaner so it draws from the cooler side might help.

I took the day off so I could get some projects done so tonight I should have some answers.

Thanks for all your input, I don't care how good you are at anything it always helps to get some fresh input to put your mind right.

Later

 

[rbohm]

8) you need a heat shield in the system. take two carb base gaskets and a large piece of sheet metal and make one. cut the sheet metal so that everything works well, but so that it also blocks heat from the exhaust manifold. that should help alleviate any issues.

 

[dagenham]

I went old scool for my vapor lock problem. They used to use a plywood spacer under the carb on the old flathead v8's. It seems to help solve the problem a little.

 

[early ford fan]

i use a power vent for a boat to suck out the heat in my doghouse.

 

[sixpony]

Since your breather has already been "modified" why not try a cold air intake, piece of flex tubing should work, also an electric fan from a salvage yard might not cost too much provided you don't choose a "hot" seller(sorry, couldn't resist), reverse the polarity and mount it as an auxiliary on the front of the rad, I may try this myself for my hot restart prob, with a thermostat and hooked directly to 12v,make it sound like onea those fancy riceburners when u shut down! Probly have to replace my motorcycle sized wally world battery tho! Seriously though I wonder if the guys running the direct mount 2bbls have heat problems or if it's mostly the old 1100's that have this issue?

 

[61econoline]

First let apologize for taking soooo long to respond. I appears I had two problems besides the vapor lock. One the ignition switch had a dead spot in the run position and Two the new ignition module probably got cooked when the engine overheated. When I tried to start the van I would get spark as I went to crank it and then nothing and also when I turned it off. So I put a run toggle switch in along with a key start switch from and old 9N tractor (Ford of course). Everything looked good but still no spark. So I broke down and put the old dizzy in with points, STILL NO SPARK!!!. I walked away. Today after I cooled down I check the wiring and found the wire to the distributor was not only loose but was hanging on by two strands. I replaced the wired and VAROOOOM. Test drive was fine, no overheating, it started after it heated up. I may put the duraspark II back in But the ignition module is going outside the dog house with heat sinks.

And yes a heat shield is on my to do list and also I thought that an electric fan behind the doghouse to draw air through it and out the floor might help keep the doghouse cool when I slow down.

Can't thank you people enough I'm taking the van to work tomorrow I'll let you know how it goes.