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Sat Aug 18, 2012 10:46 am

So I was driving all day yesterday, when I parked to go into a store the car wouldn't start when I got back. It had obvious signs of vapor lock (I used to get this a lot on my old engine), I waited a little bit and poured some water on the fuel pump and she started up and I got home with no problems.

My car is a 65, engine is a 1200cc 40hp, 28 pict, 009 distributor with a doghouse fanshroud/oil cooler. The engine was rebuilt by Car Craft in Riverside, CA back in October. I just got the engine in last week and got it running two days ago. My old engine was a 1600dp that had alot of overheating problems. The reason why I got this 40hp rebuilt was so I wouldn't have to be stuck on the side of the road anymore. I want to get this engine running cool so I won't have to deal with stuff like this anymore.

There is still a few gaps in the tin I have to fill, but nothing major, all the seals are there. I have read that without more airflow, the doghouse will run hotter in the earlier cars without the slits in the decklid. Does anyone have any experience with this? Will switching to the earlier style shroud make a big difference? Does anyone have any other advice for running cooler? I know my thermostat is working, but I'm not sure if it's opening the flaps all the way. If someone has a picture of the position of the arms of thef flaps in the open position it would be great. I might end up taking the thermostat out and wiring the flaps open if it isn't working correctly. Does anyone have any advice or suggestions?

Here's a picture of the engine, note that this was taken before I started driving it, it doesn't look exactly the same anymore.

Sat Aug 18, 2012 11:54 am

Is you deck lid vented as the dog house cooler does take more air. Try propping thedeck lid open with a soda can att eh latch area.

Sat Aug 18, 2012 12:09 pm

Make sure the total timing advance is not over 32 degrees BTDC. Get an old tennis ball and cut a slit in it. Stick it onto the deck latch hook.

Sat Aug 18, 2012 1:38 pm

Plug the hole in the rear tin or better yet dump the aftermarket one and get a 40 HP or 1966 stock one with the heat riser tube to go through that hole.

Also get hose clamps on both top and bottom of the fresh air tubes to avoid having either tube from popping loose and frying a head.

Spark plug wires are supposed to be clipped into the plastic plug on the right of the shroud. Missing the two other plugs at center and left which means more cooling air lost...

Either get a cabriolet engine lid or a tennis ball to keep hood cracked open at bottom.

Sat Aug 18, 2012 1:46 pm

ditch the fuel filter big no no
also do you have all the tins on the under side
do you have the choke wired up now couse its not in the pic?

Sat Aug 18, 2012 1:58 pm

The picture was taken before I started driving the car, I have clamps already, and oil filler with down tube, surprised no one mentioned that. The rear tin is stock and I am going to plug the hole, I doubt I could get my oil bath air cleaner (if I can find it in the garage) to fit with the carb spacer to run the hose through the tin, although I'd like to. I'll see if I can get the other spark wire plugs today, I don't think that these holes would be a big enough issue to be causing the vapor lock tho'.

Timing is set at 30 BTDC at total advance.

Sat Aug 18, 2012 2:01 pm

Lower pulley looks too small, which can mean your cooling fan is not turning at fast enough RPMs. DH had biggest lower crank pulley since 1961.

Plus if you are using too small of fan it will cause cooling problems. Biggest fan used on 1500/1600 non-DH engine was 29 mm, DH used 33, 34, and best was the 35 mm (inside measurement). Earlier fans were even thinner!

Wonder if your real problem is not vapor lock, but that the fuel is flooding the engine. Had same problem and fixed with second gasket between carb top and fuel shut off valve.

Check engine when hot next time for fuel dripping from throttle shaft ends.....

Sat Aug 18, 2012 2:15 pm

Lower crank pulley is 7 inches. The fan is a correct dp fan, although I'm not completely sure, I believe it is the 35mm. All the shroud/fan set up came from my 1600, I have the parts from the 40hp that it came with, but I've never used them.

I had fuel dripping from the throttle shafts when I tried using a 30 pict I had, I haven't noticed it yet with the 28 but I haven't driven it much yet. So you just doubled the carb top gaskets? Where is the fuel shut off valve?

Sat Aug 18, 2012 2:30 pm

In the top of the carb float chamber. With valve moved slightly more down the float pushes harder against the valve keeping it closed.

Sat Aug 18, 2012 2:33 pm

Next time you remove the shroud from the engine, measure the fan, do not go by believing.

Sat Aug 18, 2012 3:39 pm

When the engine was hard starting when hot, did you try starting it holding the accelerator pedal to the floor? I bet it would have started.

It sounds like you're doing everything right. Unfortunately what you describe is pretty common on carbureted engines when hot.

Sat Aug 18, 2012 7:34 pm

Blue Baron wrote: When the engine was hard starting when hot, did you try starting it holding the accelerator pedal to the floor? I bet it would have started.

It sounds like you're doing everything right. Unfortunately what you describe is pretty common on carbureted engines when hot.

This was what I was thinking. I am a new bug owner and was having the same type of problem with my mine after driving on hot days, shutting it down, and then trying to restart it. Someone recently covered this in another thread and even referenced the owners manual/provided a pic of the page. I tried it the next time I was out and sure enough, problem solved.

Sat Aug 18, 2012 8:31 pm

I have a '62 bug with a 1600, doghouse, etc. I use a thermostat and flaps on both of my VWs...if adjusted properly they will be all the way open fairly quickly.
I have no extra venting in the decklid / tin and it does not overheat. Runs great, city driving, even in the 100+ degree heat we have over here in the midwest summers.
Seal up all of the tin, move that fuel filter out of the engine compartment like mentioned above. Check total advance. I usually run 30 degrees max.
Make sure that the insulation on the firewall is not too close to the fan.
Hot starting can be a challenge, the "foot on the floor" method helps. Common thing on VWs.

Sun Aug 19, 2012 1:12 am

I feel like posting the picture was a bad idea, I only had the fuel filter in the compartment when I was first starting the car. Firewall is brand new and isn't being sucked into the back of the shroud. I wish this was something as simple as pushing the accelerator down, if it was I wouldn't be posting this. I literally watched vapor come out of the fuel pump when cranking over. This car isn't new to me. I spent a lot of time tracking down all the parts to make this 40hp work including all tin work, which wasn't easy to find. In the past I put in a rebuilt transmission, all wiring has been replaced including the main loom. All hard lines, soft lines, master cylinder, and wheel cylinders have been replaced. The engine is the very last thing I need to make this car drivable and I know it's running hotter then it should. I have the feeling it may have something to do with the shroud, I wish I had a temp gauge so I could test the differences between the earlier and later shrouds. Well, I'm gonna plug that hole in the shroud tonight and test drive it some more tomorrow, besides getting hot she has been doing fine, the engine sounds strong and idles fine, acceleration isn't bad and can easily go 65 on the freeways.

One thing I just noticed.. it appears my thermostat has failed and is permanently stuck in the expanded position.

Sun Aug 19, 2012 5:21 am

Too lean of an air/fuel mix will cause a VW(or any) engine to run hotter than usual.
Try the next size larger main and pilot jets-it'll use a smidge more gas,but the cooler running makes it worth it.
If your top speed is only 65 (should be 72) you could definitely be running a bit lean.
When VW initially set up the correct jetting for these motors,there was no ethanol in the gas-now that there is,the mixture needs to be a tad richer to achieve the same power output.
I re-jetted my Bug (stock 40 hp) back in about 1994 for the same reasons-top speed was down,and it was running hotter than it should-and it's been fine every since.

Sun Aug 19, 2012 7:04 am

Here in N Carolina, we have high heat and stupid high humidity.

I agree, I have found the main jets need to be a couple of sizes larger with todays fuel to bring engine temps down a little.

No where in your post do you mention... any temperature readings, either air or engine temps.

Sounds like you have a heat soak problem, more so than vapor lock. Heat soak is where after you shut your engine off, the heat it has generated transfers, and in your case, either boils the fuel in the fuel pump, or the carb.

It could be caused by higher ambient air temps, with higher engine temps.

Be sure if you have metal fuel lines they are isolated from heated metal.
NO cooling air leaks is real important.

Sun Aug 19, 2012 10:23 am

Up here in the central valley the ambient temps have been averaging about 105ish.
I have had no problems overheating with my 40.
Almost identical to yours, except a different fuel pump.
Stock shroud and oil cooler, lid not offset or propped open. The only change is that I fitted internal flap type thermostat to the stock shroud.
009 dist at 31 max
30 pict-1 as it came

Freeway run (65mph x about 30 miles) daily averaged mid 300's cht, and 200-205 oil temp at max.

Thats fairly hot, and Ive never had any vaporlock issues when I stop and start.

One thing that caught my eye in your picture is the fuel line. Its just laying on the shroud in a very hot area. The stock is a tube mounted up over the intake away from heat risers and hot shrouds.

Might make a difference. :?:

Sun Aug 19, 2012 10:53 am

I went through this for several years. It wasn't the heat. Nickel and dimed the problem for quite awhile to find out the aftermarket float was absorbing fuel, changed its weight and wouldn't shut off fuel to the bowl.I found a stock brass one, changed float and haven't had a problem for 1 1/2 yrs.

Sun Aug 19, 2012 11:01 am

Top speed isn't 65, that's just how fast I was driving, could go faster if I gave it more throttle.

I wish I had some sort of oil temperature gauge or anything, but I couldn't afford it by the end the build. I planned on putting some gauges in, I even ran extra wires when putting in the harness but for now I have nothing.

I have been thinking about the engine possibly running lean. I was thinking maybe there was some sort of air leak around the carb maybe leaning out the mixture. I couldn't find any tho'. I could try running some larger jets, what are stock in a 28 pict and what sizes would you suggest?

Earlier today I took the car out and drove for like 30 minutes, it got hot enough that the oil light started to flicker on when I was almost home. I know the oil level is good and it's not leaking.

I'll move or adjust the fuel line so it's away from the intake, I plan on dropping the engine today to pull the shroud and check the size of the fan. I might try running the 40hp shroud and fan I have to see if that makes any difference. This doghouse shroud/fan was used on this engine and my old 1600 that had overheating problems, I'm starting to think maybe the fan is the wrong size. It did look much larger than the 40hp fan tho', I guess the measuring tape will answer that question.

Sun Aug 19, 2012 11:56 am

Have you used the candy thermometer in the dipstick hole trick to see how hot its running?

Also if you take a pic of your fan in the shroud I can tell you if you have the wrong one in there. Could be a plugged up cooler too.