Intake Manifold Saga

[johber41]

There has not been a build or repair thread in a while so I thought i would share some interesting experiences.

Preface:
A log time ago (2008), but not far away, I was gifted a 1966 Manx style dune buggy built from a 1961 donor Beetle with a 1200 CC, 40 horse engine. The car was under a tarp in my neighbors yard and it had not been running since 1985. Everything was dirty and seized including the engine and trans. The car had not been attended to for many years with the tires flat and rotten and parts of the engine rusty and rotten. I had little or no experience with Volkswagen, being from Detroit left little room for foreign car hobbies, I did not understand the heat risers on my 1200 and why they were necessary. I cut the rotten riser off after attempting to patch them with copper. The whole tube was plugged anyway.

Jump Forward:
Lets get to 2018, the Buggy Roundup, and I noticed that I was getting hesitation on acceleration and asked a very competent buggy man what he thought it might be. The talented Mr Porter explained that the hesitation was likely from a bad, or miss-adjusted accelerator pump in my PICT 30 carb.

Carb investigation:
Upon getting back to Houston, I watched a lot of You Tube and then attempted to rebuild the carb. Everything went well and the was put back in and the same problem existed. i checked timing, valve lash, etc but could not cure the problem. Then I saw IT........a fuel drip below my intake just below the intersecting down pipe to the horizontal delivery system. I thought for sure I had a leak there causing air to be sucked into the intake. I also saw in a information video that the heat risers on the intake were necessary to stop fuel from puddling at the bottom of the down tube of the intake, as the fuel causes a cooling affect as it expands leaving the carb.

attached is a pic of my intake heat risers when I first tried to fix them....

[johber41]

Engine pull and intake sought:
After getting my engine out again....I pulled the carb and then the intake and saw that parts of the bottom of the tube were falling apart. It was swiss cheese when I fixed it the first time (2008) where my MIG welder would burn through it at every point. Finally I got the weld close enough that a little JB Kwik handled the rest. Well, not really!

I sought a 1200 cc single port intake and found a new replacement on Ebay and bought it, $70.00 delivered. It did not fit my engine. Its for a 1300, being a little thicker and wider. I then checked everywhere a could think of and found no available replacement. I then remembered that I had found one years ago at a swap meet and bought it for a few dollars but never really looked it over. We will call this unit #1 replacement. Old, never been painted, but lots of holes and a completely blocked heat tube. Some thin metal with holes at some elbows on the heat tube and most noted, a modified neck to the carb, Someone had bent the tube to the left a bit and re-welded the mounting port.

I sought a second replacement when i asked around and was sent to a guy in League City. This guy had lots of VW cars, vans, and parts. He sold me an intake but when I checked it out for paint, it was like swiss cheese at the heater riser elbows and the tube was completely blocked like #1. We will call that #2 Replacement.

See attached pics.

[johber41]

Started to repair these replacements by drilling out the heater tube which means cutting holes on each end for the drill and then creating a long drill with the use of a cement drill and a long hardened rod. Upon clearing the heater tube and #1 and on #2 replacement intakes, I welded them up, ground the welds even, re-welded the holes, grinder again and then some JB KWICK to seal them for sure.

I will show you the progress on both units. I know you are wondering why I am fixing two units. The answer is....I just am sine i have them anyway and it gives me choices if I should run into a problem with one or the other.

Yes, my 61 1200 cc power plant will soon have the benefits of heat risers for the intake warming needed for the fuel to act right.

[johber41]

Some more welding shots.......looks ugly but it is strong!

[Ken]

Great write up John. Thanks for sharing. I agree it's been too long since we've had some mechanical threads here. I've got something I'll post in a few days.

[johber41]

Sounds good Ken.....more to come here, waiting for some sunshine to paint the intakes and tins.

[staggerwing]

Very cool, John! I love those copper elbows on the risers. You sir, are on of those guys that can think outside the box, which is something I struggle with.

[johber41]

Thanks Richard...that was a quick fix back in 2008 when I did not even know what they were needed for. Back then I just thought it was something needed to start the engine. Eventually I removed them from the intake, welded the holes in what was left of the intake and used it like that since. Now I am going to give then engine the use of the heat risers to maybe stop some of the hesitation in my acceleration.

below are some pics of the intake replacements after grinding, filling, sanding and painting. They bot turned out to be acceptable and I will roll with the one that had the least damage. The #2 replacement from the parts place in League City seems to have the least damage, even though it was pretty rusty.

[johber41]

ps: By the way... I have a brand new, in the box, painted with grey primer 1300 cc single port intake that I paid 70 bucks for on Ebay thinking it would fit my engine. if anyone wants it for their single port I would be willing to part with it for $50.00. It will not fit the 1200 cc...its fatter in the tubing and about an inch wider with bigger ports at the heads.

[Ken]

can think outside the box, which is something I struggle with.

X2 - I don't have a creative bone in my body.

[ScottR]

John, I always enjoy reading your posts. Its like a "how to" book with step by step instructions. Great job and well done.

[Heathwerner]

Hey John, I totally forgot to check to see if I had another intake for you, sorry! Ive been super busy building my Baja Bug. I did check and I dont have one. It looks like you have done a great job fixing up the ones you found. What I do have though are the crush gaskets and you are more than welcome to a set. They have become hard to come by so I pick them up when I can. Let me know.

Heath

[johber41]

Thanks Scott....its fun so I try to relay it as such. Thank you Heath...I need the ones for the fuel side and i have the ones for the heat riser side.

Today I took advantage of the sunshine and attended to my tins. After cleaning, sanding, welding, grinding, and re-sanding, I was able to get a couple of good coats of rustolium on them.

See pic

[johber41]

Intake Saga continues....

I mock the intake manifold up by bolting it down on a crush gaskets and find that the new intake heat risers do not match up to the cannon exhaust pipes I am using. When the intake is bolted into place, there is a good 3/4 inch space between the exhaust heat riser port and the heat riser intake tubes. And...each side the space is different. While trying to figure out why, I realize that the exhaust i am using is universal for any buggy with a type one motor. Now, I have learned that the 1200 cc intake is its own animal and is not universal with any later model engines.

So....I need to invent adapters.

see pics

[johber41]

Heat Riser Adapters..

I noticed that the opening on the heat riser tubes of the intake will accept a 1/2 tube, but, the openings for the heat risers on the manifold are only 3/8 in size. I was now in search for a copper tube adapter that could match the intake riser opening with a 3/8, to fit inside the 1/2 inch tube, while filling being accepted by the exhaust 3/8 opening with a flare tip maybe a little bigger than 1/4 inch. They would need to be cut down to equal the gap on each side and then crush down when bolted to form a decent seal.

I found , what plumbers normally call, air hammers to help with back pressure on in coming water to sinks etc. They had the perfect ends for me to modify into adapters.

[johber41]

Once the adapters were bolted in place, I went to work on inventing some spark plug cable organizers to be attached to the new intake. Each cable would be wrap tied to keep it clear of the wiring and make just look better.

Used 3/4 " pipe clamps with attached L brackets.

More later....

[staggerwing]

Bravo! Good job, sir! When do we get to fire it up?

[johber41]

Thanks Richard...I hope soon. I had a revelation during the night, since i do not sleep anyway, and thought how much I did not like the mismatch on the heat risers, and how i was going to have to use a lift adapter on the carb, which I ordered, to get the carb linkage off the voltage regulator mounted on the top of the generator. The use of adapters is ok if its all you have, but, I have another intake I cleared, welded, and painted.

I disassembled the engine once again and removed the intake that had the mismatch. I then completed the repairs to the other intake unit, sprayed it with heat paint and then attempted the install. It fit like a glove.

I restricted the heat with a restrictive gasket to the side that had the most welding on the riser tube. Bolted the other straight in and everything looks great. I re assembled the engine and its ready to be tossed back in the buggy.

[johber41]

Installed my engine and it fired right up.....as I was getting my timing light out I could smell gas leaking....my rubber fuel line which runs from the end of my metal line, just in front of the swing axles, was leaking. As I tried to repair it, it just kept splitting and leaking. I drained the remaining fuel in the tank and removed the rotten line.

A trip to the oreillys resulted in new fuel line and filter. I installed the fuel line and just before putting gas back in the tank, I throttled the carb a few times and watched the remaining gasoline from the float bowl in the carb leak out of my passenger side heat riser. As I sat there and watched that f&?&!$ (type swearing) leak, it reminded me why I have not had heat risers on the car for the last ten years. Somewhere in the inside of the intake there is a breach between the fuel delivery and the heat tube......GREAT!

Knowing that the car should be catching on fire momentarily, I shut it down and got on the phone looking for more potential intake manifolds. I may even build one if I have to. Headed to Pasadena to look at a few ......intake saga to continue!

[johber41]

I traveled to Pasadena today and met with the good folks at the Bug-O-Holics VW company located on Heights street. They were able to find a decent intake unit for me with plenty of good metal on the riser elbows. The unit was plugged but that was easy for my long cement drill. After clearing the heat risers and the horizontal heat tube, I ran an old piece of cable through both sides and did some additional cleaning. to close the holes, I kept my welder away and patched the drilled access holes with metal patches and JB Kwick. Just in case my welder caused the breach in the last unit, which I doubt!

Paint it up tomorrow and get ready to pull the engine once again.

[Heathwerner]

Hey John, your persistence is admirable. It looks like you may have finally found what you need to get your heat risers installed. Henry over at Bugaholics is always a great go to guy for help, he has helped me find those unusual hard to find parts several times. I know its probably a little late to mention it but they do make replacement heat risers and you can usually manipulate them enough to get them to match up. It looks like you have a handle on it now. Good luck!

Heath

[johber41]

Thanks Heath.....you are right, Henry told me this unit has been hanging in his shop for thirty years. I have seen the replacement risers for the dual ports, and I thought about chopping them off the last replacement unit and replacing them with those but the problem is that I just do not know where the breach is and believe it might be in the middle of the intake, inside the aluminum heat sink. (Aluminum overlay in the middle).

Feel better about this unit. Way more metal on the riser elbows.

[johber41]

Replacement #3......holes patched and JB Weld hardened. Painted it with 500 degree engine paint.

After allowing the paint to dry for a day, I plugged the neck and filled the fuel side of replacement #3 with water. I could not find any water transfer to the heater side.

I emptied the water and filled the fuel side with blaster penetrating oil. An hour later I emptied the oil out and noticed it had dissolved lots of rust. Repeated the steps 3 times and then let it drain. Pumped WD40 in it to displace the oil and water and left it for a while.

It appears that the fuel side is clear and not leaking. I never found any sign of water, blaster, or WD40 leaking from the risers. Sprayed engine gloss paint into the heater tube and after allowing it to dry, blew compressed air through and found the heater side still wide open. Tomorrow starts the engine removal and intake replacement.....AGAIN!

[johber41]

Replacement #3 has turned out to be leak free and still has healthy amounts of metal on the riser elbows. I have also come to the realization that while pulling the engine this time, I am going to complete some maintenance stuff that has been looming for years. While able with the engine out, I am going to replace my leaking swing axle grease boots and replace my sketchy starter. I have had the boots and starter in my inventory for years.

I replaced the intake (AGAIN) and found that this intake does not want to match up with my exhaust heat riser ports. I re-installed the adapters I developed two intakes ago and the units seems to be ready.

[staggerwing]

What’s the claw hammer for? Be gentle!

[johber41]

Good eye Richard......had to push one of the adapters over a bit while tightening down the heat risers.....

[johber41]

Back on the buggy since I have been able to escape the winter vortex in Michigan for a while.

Started with obtaining a new main jet, 120, for my PICT 30 Empi carb. I purchased 120 and a 117.5. I'm going to see if I am thinking this correctly.

When I first received the buggy, it had on-board all OEM equipment from 1961. As the years went by, I have tried to improve with introduction of a PICT 30 carb over the worn and leaking PICT 28.

I changed the distributor from a big-cap with vacuum advance to a .009.

I believe my better option is to move backwards now by replacing my distributor with the rebuilt big cap. Then I rebuilt the vacuum line to the carburator adding a steel line with the reverse P-trap. I replaced the bad main jet with a new 120. I have a 117.5 just in case it needs to be down sized for the 1200.

Lets see what happens.

[Heathwerner]

Welcome Home John. Let us know how it goes. Good Luck!

[johber41]

Thanks Heath.....check your personal messages...left one for you.

[johber41]

In conclusion.....went OEM as much as is possible. I have had a positive result and drove the heck out of it on Saturday including cruise night in Kemah. Ran great and electrical system was healthy and flawless with constant and even charging. I can tell the generator is a success due to being able to shut the battery off while running and still run the car with the lights without fail.

The new intake with a corrected heating tube seems to be helping. I at least know that there is no breech or vacuum leak.

The Bosch big-cap distributor has evened the engine out and though it might not be as peppy as it was with the .009, it is not hesitating. I have it timed at 10 degrees BTDC as is listed in the manual for the 1200 40 horse.

New wires and plugs...everything good. I even had it over 60 mph, which was always a stretch in the past.

Thanks for all the advice and thanks for following along.