### Help Support Homebuilt Aircraft & Kit Plane Forum:

#### Vigilant1

##### Well-Known Member
It takes a lot of experience, patience, and time to get a reliable acft engine from one that has been used or abused in a car with an unknown history. In that first post, Pops says he found a slightly bent conrod and some other things out of whack.
Lots of things would need to be precisely measured and assessed, and some of those assessments are subjective. This is, after all, to be an airplane engine with all that entails.
A used VW based airplane engine might be slightly less worry than a typical car engine if it was flown and maintained by someone who is trustworthy and competent and if you can hear it run, do a leakdown test, take a look at the things that can be readily seen, etc.

#### don january

##### Well-Known Member
Log Member
Do you buy stuff like dipsticks/tubes, rocker cover bails etc. or do you recycle that stuff?
I'm not sure if you are directing the question to pops but I think he may agree with me in saying that any part from a VW engine rather for air or ground use if you find a bail / cover / push rod tube and so on that seals good you should hang on to them. Like pops I've bought new and had to throw on the bad shelf and reuse old stuff that was proven to work well and hold up.

#### blane.c

##### Well-Known Member
HBA Supporter
So collecting for the ancillary stuff and occasional "find". I was wondering because the cheapest used whole engine I could find was 50$and dang! It's plumbers crack ugly. Seriously. Looks like it was pulled out of brackish water (just like a plumbers crack). 200$ for a 1200cc seems like the best thing near here and it is not suitable for modifying. So most are selling around 300$to 350$ for whole engines and they all have dual port heads.

So figuring out which ones have sheet metal and ancillary items worth spending any money on, that is an education in and of itself, let alone assuring all the proper modifications are accomplished on a build.

Cheap may be the attraction for VW power, but you are sure going to have to put in the sweat equity. I liked my little bug I had when I was 18-19 years old out in Arizona, 36hp. I used to joke, put it in reverse and it would back up a tree.

#### Pops

##### Well-Known Member
HBA Supporter
Log Member
The first engine in the SSSC was a 1200 cc, 40 HP VW engine. Put the word out in the area that I was looking for a VW engine. Found one a couple miles away that was outside laying on the ground under the overhang of a storage building. Owner wanted $40 for it. One piston was frozen in a cylinder. I got it apart and the insides looked new and measured new. I used the case, crank, rods, cam and lifters and heads. Rebuilt the heads, took the case and crank, cam lifters to my VW machinist and had him polish the crank journals, rebuild the rods and made the rods a match set in every way. Bought a new set of pistons and jugs and cleaned, and balance the pistons within one gram. Assembled the engine and checked the clearances. New valve guides and valves and hand lapped to the proper valve /seat contact width. Checked deck heigth, and set the CR to what I wanted. Etc, etc. I bought the carb, prop hub and mag drive from GP's and a friend gave me a new VW Slick mag and harness that he didn't need. WIth a Culver 54"x 22 pitch prop WOT on climb out was at redline of 3600 rpm and I cruised at 3200 rpm. Flew it for 32 hrs. Great running engine, with a cruise of about 68 mph and a ROC of about 600/650 fpm. I didn't want to run the engine that hard for long life so I built the 1835 cc, 60 hp engine for it. Perfect engine for the airframe. Last fall a man had 2 VW engines for sale, one a 1966 50 HP, and the other a 1200 cc , 40 hp. Told me on the phone that he wants$50. I thought he meant $50 each and when I went to buy them he said the price was$50 total for the two engine. Both have a piston frozen in a cylinder and the 40 Hp had a broken piston and a slightly bent rod.
I still have VW engine parts in boxes from where I used to rebuild VW engine as a side business, so I have lots of the small parts needed for several engines.
Think I'll use the 1200 cc, 40 Hp engine on either a VW trike or a Pipe-Buggy. I bought a 1973 VW rear suspension and transaxle for what ever I decide to do.
In the meantime I'm working on a 2180 flywheel drive aero VW engine. I have most parts to finish it except for a pulley end mag drive, No One make such a thing. So i have some of the parts made for such a drive. Engine will have a bed mount, so most of the flywheel end flange will be cut off to same weight. Have a set of single port heads drilled for dual ignition but will be non-electric. The mag will be the main ignition and the electronic ignition will come one when the fire to the top mag plugs stop firing after .5 seconds and will be powered from the small 12 battery that is also used for the handheld radio and gps. If the mag go's out, the engine will still run enough to get to the nearest airport. I'll do test to get an idea of how long and make a chart by battery voltage. May have to install a slightly larger cap battery.
Talked to much, think it's bedtime. Goodnight.

#### N8053H

##### Well-Known Member
Pops nice write up. Let me ask, what HP does my little 1700cc engine make? I estimate it to be around 50hp. It also has no electric system and a mag. But only a single ignition. I would like to add a second ignition like you mention. I should have had those heads drilled for dual plugs. Live and learn I guess.

You will see I changed out that oil line. But I do not like this setup. I have had one of these metal oil lines on my 1/2 vw break on me. I had just landed and noticed a little drip of oil coming off this line. I stick up finger out to wipe the line barely touching this line and it broke right off. Why I like the plastic line. But I do worry about melting one of those plastic lines. What to do?

This line will brake because of no support and that bend. The support IMHO is to far away from the end of this line to help in removing any vibration from that line. What do you think?

On this engine I will be checking or running her to make sure the oil cooler gets warm. If it is indeed getting hot or warm I am then shutting the engine down. MY break in of this engine will happen this fall after the outside temps go down to help keep oil temps in check while I brake this engine in. No need in doing this brake in during the hottest part of the year. I can wait a few more weeks or a month or two if needed.

#### blane.c

##### Well-Known Member
HBA Supporter
My old Aeronca had little copper Primer lines to each cylinder, they cracked so often I carried a small bag of ferrules in the glove box. It was not uncommon to replace a ferrule during preflight or if I landed out somewhere before I flew home . They always cracked right there were the line goes into the nut. I think the lines need to be coiled just before going into the nut and need a re-enforcement sleeve.

#### Pops

##### Well-Known Member
HBA Supporter
Log Member
My old Aeronca had little copper Primer lines to each cylinder, they cracked so often I carried a small bag of ferrules in the glove box. It was not uncommon to replace a ferrule during preflight or if I landed out somewhere before I flew home . They always cracked right there were the line goes into the nut. I think the lines need to be coiled just before going into the nut and need a re-enforcement sleeve.
The 1/2 VW has a lot more vibration than the 4 cylinder. I have never had a 1/8" copper line break, but I always support the line and bend loops at each end.

1200 cc VW engine, about 40 Hp straight drive with prop.
1300 cc VW engine, about 45 HP straight drive with prop.
1600 cc VW engine, about 50 hp straight drive with prop.
1700 cc VW engine, about 54 hp straight drive with prop.
1835 cc VW engine, about 60 hp straight drive with prop.
Lots of variables, so Hp can vary a lot if everything isn't perfect, on small engines a little lower on compression, timing off a little , etc means a lot. So in real life expect a little less.

BTW-- The Kitten you sold my neighbor. He sold it without flying it, just taxied it and is flying a Challenger . I liked the Kitten, nice little airplane. He had tried to fly a taildragger before and gave up.

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#### BBerson

##### Light Plane Philosopher
HBA Supporter
How did you narrow the valve seat contact width to smaller width (about .063") with hand lapping?

#### Pops

##### Well-Known Member
HBA Supporter
Log Member
How did you narrow the valve seat contact width to smaller width (about .063") with hand lapping?
I did not narrow the valve seat contact, I lapped until I had the width required. They are narrow to begin with and as you lap the width gets wider and the head of the valve sets a little deeper in the seat. And you are correct, its about .063-.065, if I remember correctly.

#### BBerson

##### Light Plane Philosopher
HBA Supporter
I did not narrow the valve seat contact, I lapped until I had the width required. They are narrow to begin with and as you lap the width gets wider and the head of the valve sets a little deeper in the seat. And you are correct, its about .063-.065, if I remember correctly.
So you had almost new width. Mine are always worn out to about .125" seat width. I had used my friends valve grinder in the past.
Now I need to find my own tools. Was thinking of getting Nuway cutters.

#### N8053H

##### Well-Known Member
The 1/2 VW has a lot more vibration than the 4 cylinder. I have never had a 1/8" copper line break, but I always support the line and bend loops at each end.

1200 cc VW engine, about 40 Hp straight drive with prop.
1300 cc VW engine, about 45 HP straight drive with prop.
1600 cc VW engine, about 50 hp straight drive with prop.
1700 cc VW engine, about 54 hp straight drive with prop.
1835 cc VW engine, about 60 hp straight drive with prop.
Lots of variables, so Hp can vary a lot if everything isn't perfect, on small engines a little lower on compression, timing off a little , etc means a lot. So in real life expect a little less.

BTW-- The Kitten you sold my neighbor. He sold it without flying it, just taxied it and is flying a Challenger . I liked the Kitten, nice little airplane. He had tried to fly a taildragger before and gave up.
I agree about real world HP. I may be lucky to be pushing 50 HP. But she does a great job flying this Cygnet airplane. Fly her as a single seat and the performance is very good. I fly her alone and really enjoy it.

It just so happened I had another of those Kittens land in my Lap. I sold her to a good friend for what I paid for her. An Aviator helping out another Aviator. He flew two strokes and wanted a good four stroke, but everything was out of his price range. He also did not have to go get it. It was delivered to me free of charge. This one was Brand New and only flown once about ten years ago. It has flown a few times now. We are still replacing things on it from age. The Shock Cords was just replaced a few weeks ago. He went through the fuel system and everything else that needed looked at. We are almost done with it.

#### Vigilant1

##### Well-Known Member
Opinions on 94mm cylinders?

When I looked at the cost-per-HP of the Casler 2400 (really, 2387cc) engine, it looks like quite a pretty good bargain. On a bang-for-the-buck basis, it's not too far behind a hand-propped 1835cc, but it has dual ignition, starter, etc. As we've discussed, asking a VW to regularly put out 85HP seems like a stretch. But an engine like this run at lower RPMs and HP output might prove to be pretty trouble free, and the 85 HP adds no weight and only \$300 to the 2180cc (76 HP) engine. And if you >needed< the additional HP in a pinch, it would be there.

Concerns:
- 94mm bore: Whenever I see the cases machined for the 94mm pistons, it just doesn't look right. The amount of magnesium left between the studs and the cylinder bore is tiny, it seems sure to crack, eventually. True?
- 86mm stroke: Is this a concern from a reliability/longevity standpoint? The largest crank Great Plains sells is for an 82mm stroke. Revmaster's largest airplane engine stops at 84mm, I wonder if there is a reason (Joe Horvath has certainly done a lot of more extreme strokers for his VW dragsters and performance car engines, but he doesn't sell 'em for airplanes).

I haven't heard any concerns/problems from the few folks I know who fly Scott's 2400 engine, they like the power and say it is very smooth.

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#### blane.c

##### Well-Known Member
HBA Supporter
A-pistons and B-pistons, are there any C-pistons? Or is it just not going to happen getting the pin closer to the top?

Can the cylinder skirt be thinner? To facilitate a 92mm cylinder in a 90.5mm spigot or a 94mm cylinder in a smaller spigot? Or is that just a bad idea?

#### pictsidhe

##### Well-Known Member
It's a fair bet that VW racers have explored the limits over the last 80 or so years.

#### blane.c

##### Well-Known Member
HBA Supporter
Yeah that's why I ask, it's already been done, how'd it workout?

#### blane.c

##### Well-Known Member
HBA Supporter
Is Revmaster the only place to get the beefed up crankshaft and bearing ? All others being pressed on?

#### Vigilant1

##### Well-Known Member
Is Revmaster the only place to get the beefed up crankshaft and bearing ? All others being pressed on?
No. The Force One prop hub and bearing sold by Great Plains Aircraft Supply and used by Scott Casler/Hummel is not a shrink-fit hub, and the Force One includes a beefed-up bearing to replace the stock #4 bearing.

Here's more on VW cranks, metalurgy, and the history of the Force One hub. http://www.greatplainsas.com/phubhistory.html
Here are the installation instructions: http://www.greatplainsas.com/if1ph.html

I would >strongly< recommend that anyone building an aero VW engine of any type get a copy of the assembly manual and/or DVDs sold by GPAS. It is money very well spent and answers a lot of questions that anyone would have. I have no financial interest in GPAS, just a happy customer.

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HBA Supporter
Thank you

#### N8053H

##### Well-Known Member
Update on my VW engine. I flew her last evening. Oil temps stayed at 190 degree's. Once landed on roll out I noticed oil temps of around 210-220. My take on this. This engine needs broke-in in the air and stay off the ground until broken-in.

#### blane.c

##### Well-Known Member
HBA Supporter
Update on my VW engine. I flew her last evening. Oil temps stayed at 190 degree's. Once landed on roll out I noticed oil temps of around 210-220. My take on this. This engine needs broke-in in the air and stay off the ground until broken-in.
You are going to need to put a "refueling aircraft" up occasionally. Wouldn't hurt if they could throw you a bottle of water and a sandwich from time to time as well.