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Engine test stand project

18806 Views 122 Replies 31 Participants Last post by  RallyBob
Recently inspired by Viny Charb's engine build (and engine test stand he built), I decided to start building my own version of an Opel specific engine test stand.

In truth I've wanted to build one for 20+ years. Roger Wilson built a very nice test stand ten or so years ago which really came in handy when he was building and selling engines. I got a lot of neat of ideas from that too.

But since Ive been doing a lot of shop cleaning lately I started remembering that my memory wasn't as good as it once was! Previously I could look in my shop or my barn and tell you the mileage and condition of any engine that happened to be sitting there, and the running condition it was in before it got put in storage. Now, after 30 plus years of collecting parts and 30+ years of getting OLD, my memory isn't as sharp as it once was!

In addition, it's just nice to be able to test fire a newly built engine and break in the cam, as well as ensure there are no coolant or oil leaks. Much easier to fix on an open test stand than in a car!

So, without further ado, here's my own version of a custom built Opel engine test rig. I'm building it as good as I can on my budget, since I don't intend to build another one any time soon. I'm using as many new items as possible, because I hate the thought of damaging an engine because I cheaped out. I hope to have the majority of the work done in 1-2 weeks, as time allows.

This is yesterday's progress report.

The first item I built was a fuel tank. I could have used a plastic gas can or bought a metal lawn mower gas tank, but I couldn't find anything I like dimensionally. I wanted the tank to fit the confines of the test rig. I wanted a threaded filler (no fumes), and I wanted a drain petcock, so I can empty the fuel between tests easily. Modern gasoline sucks in terms of storage life!

I made the fuel tank from some .083" thick aluminum diamond plate scraps, and a threaded filler neck I got from Speedway Motors a few years ago but never used. Capacity is just over 1.5 gallons (231 cubic inches). Here is the fuel tank amidst some of the tubing I've started to cut for the test stand frame. I'm using 1.5" x 1.5" square tube with a .095" wall thickness. I will be using a Facet electric fuel pump mounted directly below the fuel tank.



Here is the mocked up engine I'm using. Note the utilization of a bellhousing, as I needed a good place for a rear mount, and I didn't want to expose myself to the spinning saw blade of death known as the flywheel ring gear while running an engine.

I set it at the angle and height which I thought was most useful for me, and started designing the frame around these requirements.



Here are the engine mount brackets I'll be using. They are early Manta/Ascona brackets. Unlike a GT's, they are symmetrical in length, but the bolt hole locations are NOT. So I welded up and redrilled one of the holes so that they are now symmetrical. Easier this way, less chance of screwing up. The actual rubber engine mounts are some cheapo 'hot rod' mounts I also got from Speedway Motors for $19.95 per pair. Very compact, and should not bounce around much.

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The rear engine mount will be made from these parts. Some 1/4" thick angle iron which bolts to the bellhousing, and some rubber isolation mounts I got from McMaster-Carr. Then the steel tubing which will be welded to the test rig framework.





Fitted to the bellhousing's lower bolt holes with 10mm bolts.

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Some other accumulated parts.

The VDO guages are all from a Kadett project I never got around to. Brand new, but 15 years old! The Autometer tach is also brand new, but from my cousin's car he parted out in 1995. So again, brand new, never used! But old stock. I already had the fuse block, so the only thing I recently purchased was the Longacre switch panel. It's got an ignition 'on' switch, a start button, and I'll be using the other auxiliary switches for an electric fan and for the electric fuel pump. I also have in my possession a battery master kill switch I'll be using on the control panel. It'll make wiring easier since I won't have to disconnect live battery cables to prevent arcing.



For cooling, I figured overkill was better than 'just enough'. The electric fan was something I bought about 20 years ago but never used...it was just too big for my needs at 16" across the blades. But it has a ton of airflow capability, and since the test stand doesn't drive down the road getting cool air, bigger is better in this case. I bought the radiator recently from Speedway Motors. It's an all-aluminum stock car style radiator that's 19" tall x 22" wide, for $115.99. Not a bad deal!



That's it for now.
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I went all out when I built mine. I decided to make it only for Opel engines as well, so that I could break them in before shipping, or testing. I have set mine up for fuel injection, or carbs with either mechanical or electric pump. I actually have one of Roger Wilson's engines on it right now. I would say it was an investment to build, but it did pay off. I have run about 5 engines on it. I sourced a fuel tank from summit and removed the foam, radiator is from the civic with electric fan already mounted, an electrical enclosure with some VDO gauges I already had, and an aluminum truck gauge panel that I had been hanging onto for some years. I would say for the engines you build, it will come in very handy

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Stand

I know an engine you can test it with
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I know an engine you can test it with
That's on my "to-do" list Jim!
Bob I'm so honoured to have inspired you in one of your endavours.:D Can't wait to see how it all ends up. My test stand was ment to have a life spand of only a few months. So how cool it looked was not a priority. But man, does it function well. It's always worked flawlessly and I've never had to do any modifications or repairs after 4 hrs of accumulated run time. I've had so much fun learning, building, and using it.:)
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Yesterday fabrication started in earnest. It went slower than usual because my 14" chop saw blade is totally shot. I had to cut everything with a 4.5" cutoff wheel, including the miter joints. It came out accurately, but it was slow going.

I am TIG welding everything as I don't care for the smoke and spatter of MIG welding. While the TIG process takes longer, one advantage is a smaller weld bead with excellent penetration. The TIG weld is also softer, so in reality the time I spent was less than if I had MIG welded, as I only needed to sand down the welds with a disc sander. No grinding for hours needed! I wanted the test stand to look clean and smoothed out, as it wlll get powdercoated when it's done.





I spent a couple of hours completely cleaning off my welding bench so I could clamp the steel tubing down to make sure everything stayed square while welding.





I used 4" diameter soft casters with locks. The locks prevent the casters from both rolling and turning. Rated for 300 lbs each, so I'm pretty well covered for an Opel engine. My time spent jigging the framework proved worthy, as there was no teeter-totter effect when I bolted the casters on!



Here you can get a sense of the scale of the test stand. The overall height is 30" with the casters, the total width is 30", and it's 40" long (so far). It will get longer when I add the control panel. The engine is at the height it will be in the stand, and is perfectly leveled fore/aft and side/side.

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A closeup of the fuel tank I built previously.



Filler detail:



The rear engine mount is being mocked up here. I will be welding it in place today. Note that by dropping the crossbar that the mount attaches to, I can allow for virtually any size or configuration of exhaust system on a test engine.



I spent the rest of the night figuring out the locations of the accessories. Here are the radiator and fuel tank's approximate locations.

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Those welds are a thing of beauty.
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I don't guess it's very important since there's no drivetrain but.... The one time I had to fabricate engine mounts for a circle track car, I placed the head w/intake so I could make sure the carb would be level. Don't know if it was smart or not but it seemed to work.

Harold
Bob, you never fail to amaze me.. :yup:

Am I correct to assume that this is a test stand, for you and no one else will see it.. ?(other than us here..?)

Yet you are proud that you saved "HOURS" of grinding the MIG welds by TIG Welding.. and even then went and sanded them down anyway. On what basically is a tool, that only you will see.. ? Where basically if you had exposed welds it really wouldn't matter..? (BTW won't even go into how nice the welds themselves are anyway).

There is attention to detail, there is fanatical attention to detail, then there is Bob. :notworthy
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I don't guess it's very important since there's no drivetrain but.... The one time I had to fabricate engine mounts for a circle track car, I placed the head w/intake so I could make sure the carb would be level. Don't know if it was smart or not but it seemed to work.

Harold
I had considered the engine tilt factor (especially a GT's), but given the rpms the engines will run at and the fact this test stand will probably never pull many lateral G's (probably...:D), I'm not that concerned.

I just checked the rearward tilt in my dad's GT and it's all of 3.6 degrees. If that was a genuine concern I guess I should just park my hillclimb car project since it obviously will never run up hills!
Bob, you never fail to amaze me.. :yup:

Am I correct to assume that this is a test stand, for you and no one else will see it.. ?(other than us here..?)

Yet you are proud that you saved "HOURS" of grinding the MIG welds by TIG Welding.. and even then went and sanded them down anyway. On what basically is a tool, that only you will see.. ? Where basically if you had exposed welds it really wouldn't matter..? (BTW won't even go into how nice the welds themselves are anyway).

There is attention to detail, there is fanatical attention to detail, then there is Bob. :notworthy
Well, I have no intentions of building another test stand. I figure if when I'm 70 years old I can look at it and not be disgusted with my work then it's a job well done. Nothing wrong with pride in craftsmanship, I feel it's severely lacking in today's youth for the most part.
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Well, I have no intentions of building another test stand. I figure if when I'm 70 years old I can look at it and not be disgusted with my work then it's a job well done. Nothing wrong with pride in craftsmanship, I feel it's severely lacking in today's youth for the most part.
True.. but this:



Shows a level of skill I can only dream about, and definite pride in your work.. those welds are amazing



This.. shows all the above.. and "Maybe" a touch of OCD :)



:haha:
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Yea, well, that's my cross to bear!

When I was 12 years old I built a model for a contest. It was a '68 Mustang in 1/24 scale. I made it in three days, all after school hours. I went as far as to make plug wires, battery cables, brake lines. I sliced pieces of solder and glued them to the wheels as balance weights. Added valve stems. Legibly painted the dials and numbers on the dashboard gauges.

The coolest feature was the antennae on the fender. Sliced a round-head plastic pin head in half and glued it to the fender top. Inserted a fine gauge brass wire into it then superglued a smaller guage brass wire on its end to that. On top of that, the ball from the tip of a fine-point pen. Painted it silver. Looked just like a telescoping antennae. I ended up having to enter it in the adult class as the shop owner refused to believe a 12 year old built it. Still placed 2nd place in the adult class. It was the last model I built.
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Well, I have no intentions of building another test stand. I figure if when I'm 70 years old I can look at it and not be disgusted with my work then it's a job well done. Nothing wrong with pride in craftsmanship, I feel it's severely lacking in today's youth for the most part.
Ii it's worth doing it's worth doing right
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Something I do regret of my set up is the "cute" 1 1/3 gallon gas tank I bought new for 5$.
I'm constently refilling or running out of gas! I'm surprirsed how of of a pain it became. I hope you have atleast 3 gallons capacity. Just saying...............
Looks great. We have one of those cheapo ones. Haven't used it yet due to a healthy fear of neighbors. ;)

But one question, that motor sits pretty high. Wouldn't lower be safer. With a blip of the throttle it would seem that whole thing could end up on it's side.
Something I do regret of my set up is the "cute" 1 1/3 gallon gas tank I bought new for 5$.
I'm constently refilling or running out of gas! I'm surprirsed how of of a pain it became. I hope you have atleast 3 gallons capacity. Just saying...............
My tank is a little over 1.5 US gallons. Since my intent is merely to check out if an engine leaks or has any funny noises, and to break in camshafts, it should suffice. If you're running out of fuel in 30-40 minutes of running time at high idle speed your fuel economy is not very good!
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