Engine Stand for 8 Liter Bentley Engine From 1928

About 8 months ago I got a call from a guy who was restoring an 8 liter engine from a 1928 Bentley. He urgently needed a custom built engine stand because the Bentley engine was too large for standard engine stands, and he asked me to design and build it.

- The engine stand had to be able to roll to different locations in the workshop.
- It should be possible to flip the engine upside down in the engine stand to work at the bottom side of the engine.
- It should be possible to raise and lower the engine in the stand to compensate for the fact that the center of gravity changes when part of the engine is removed.
- The legs of the crane should fit under the engine stand so the crane can be used to lift the engine from the engine stand for mounting it in the car.
- And the entire engine stand had to be ready within one week.

I liked this a lot so I started immediately and managed to get it ready one week later. The guy was very happy with this engine stand and he asked me if I could also assist him with the restoration. I immediately said "yes" and helped him with this project in the past 8 months during 1 or 2 days per week. Now we just finished the restoration and the Bentley is ready. The engine runs smoothly and the restoration was a success.

In this Instructable I would like to share with you how I designed and built this engine stand and how we used it.

I hope that you will enjoy this Instructable.

- Square tubing made of carbon steel 50x50 mm (2x2") with a wall thickness of 4 mm (3/16"). Total length approximately 18 meters (60 feet).
- Carbon steel pipe 50 mm (2"), total length is 60 cm (24").
- Brackets for 50 mm (2") pipe, 4 pieces
- Carbon steel pipe 20 mm (1"), total length is 80 cm (32").
- Steel plate 30x40 cm (12x16"), thickness 10 mm (1/2").
- Steel plate 12x130 cm (4x52"), thickness 6 mm (1/4").
- Threaded rod M16, total length 100 cm (25")
- Bolts M16x80, 4 pieces.
- Washers M16, 8 pieces.
- Nuts M16, 16 pieces.
- Bolts M10, 36 pieces.
- Washers M10, 36 pieces.
- Nuts M10, 36 pieces.
- Paint, gray, 1 can.
- Casters for heavy loads, 4 pieces.

Before I started to build the engine stand I thought about the design. I almost never make a drawing of my designs, because I see in my mind how I want to make it. When I have a clear picture in my head I will immediately start making it. Therefore I cannot show you a drawing, but I can show you photos of the final result.

In the next steps I will show the different aspects of the design in more detail and how I built it.

This engine has three engine supports, one at the front and two at the sides of the engine. In the car the engine sits on the chassis on these three supports. On the first photo I indicated two of the supports by an orange arrow. The third support is now not visible because it is behind the engine.

I based the size of the central section of the engine stand on the location of these three supports. I made this central section by cutting the square tubing to the required size and I welded it together. This central section is indicated by the green curled line.

You can see that this central section is a rectangle with an additional small rectangle as extension at the left side. This extension is needed because the crankshaft of the engine sticks out. If I would not have included this extension, it would not have been possible to fully turn the engine upside down in the stand because the crackshaft would collide with one of the vertical tubes of the engine stand.

On the first photo you see the red legs of the crane just behind my feet. I was tightening the last bolt before we lifted the engine from the engine stand to place it back in the car. On the second photo we just lifted the engine from the engine stand. If the ground clearance of the engine stand would have been lower, the legs of the crane would not fit under the stand and it would be much harder to position the crane.

(These photos also show how big this engine is and that is why it does not fit in the standard engine stands.)

To get enough ground clearance I measured the height of the legs of the crane and checked what height I would get from the casters.

I used quite large casters so they would give some ground clearance and also they would not easily get stuck by a nut or bolt on the floor. I used a type which is suitable for heavy loads as the total weight of the engine stand with engine is quite high. They can also swivel and they can be locked which prevents the engine stand from moving when that is not wanted.

The ground clearance from the casters alone was not enough to be able to fit the legs of the red crane under the engine stand. To increase the ground clearance I added additional short pieces of square tubing at all four corners. You can see them indicated by the orange circle.

Here you can see that the engine can be turned upside down in the engine stand. This rotation is made possible because I used a round pipe in pipe brackets.

I used a thick steel plate with 2 slots so the central section could slide up and down in the slots. At the correct height the bolts that go through the slots have to be tightened. Since the engine is heavy I added two M16 threaded rods of 25 cm (10") each to help with raising and lowering the central section through the slots.

Suppose we wanted to raise the engine. First we would loosen the bolts that go through the slots. The engine would not yet move because it is held in place by the 10" long threaded rods. Then we would loosen the top threaded rod and tighten the bottom threaded rod a bit at a time. That raises the entire central section of the engine stand including the engine.

This way the working height can be adjusted but more importantly it helps to allign the center of gravity with the rotational axis. Turning the engine upside down works best when the center of gravity is at the same height as pivot point. And since we removed and reinstalled large parts of the engine during the project, the center of gravity of the engine changed several times.

I built the engine stand in my garage but had to transport it to the garage where the Bentley was, which is about 1 hour away from where I live. I do not have a van or a truck and I wanted the engine stand to fit in my car. I therefore used some bolted connections, so the engine stand can be dismantled for transport. You can see the result on the photo and it did fit.

At the start of the project I cut all pieces to the right size. I mentioned the length of the parts on the photo.

Originally I made part B too short and part A too long. That would make transportation of the finished engine stand more difficult so during construction I decided to make part B 150 cm (60") and part A 10 cm (4").

I had to make many connections at a 90 degree angle. Since it is not very easy to cut two parts at exactly 45 degrees with an angle grinder, I decided to cut both parts as shown on the last photo, so both ends are cut at a 90 degree angle and one end has a kind of flap. This method makes the cutting much easier and the result after welding still looks good as there are no openings on the tubes.

When measuring a piece with the flap an extra length of 2 inches should be added for each flap.

There was a lot of cutting for this project. I cut everything with an angle grinder as I did not have a bandsaw for metal.

Of course I worked with the lights on in the garage during cutting, but for the photo I turned some of the lights off so the sparks are really visible on the photo.

I also recommend using a nose mask while cutting. You can see how dirty my mask was after cutting everything.

There was quite a lot of welding involved to build the engine stand. I partially MIG welded and partially TIG welded it. MIG welding is faster, but in general TIG welding looks better. (At least that is how it works for me, because I have much more experience with TIG welding than with MIG welding.)

I think the photos I showed in this Instructable so far, make it quite clear where most of the parts have to be welded. However, some parts might not be fully clear yet, so in the next steps I will show the construction details of the somewhat more complicated parts.

For those of you who do not know what flanges are: flanges are circular or square pieces of steel which are bolted together to join two sections of piping or square tubes. Flanges are used a lot in the industry to connect components in such a way that dismantling for maintenance or transportation can be done without cutting and welding.

I used this principle in the bottom section of the engine stand. That made it possible to dismantle the engine stand into several flat pieces, so I could transport the engine stand in my car. Also if the engine stand will not be used for a long time, it can be dismantled so it does not need a lot of space to store it.

To make the flanges I cut squares from a steel strip, drilled holes at all four corners and welded the flanges to the square tubing. I advise to drill two flanges at the same time so the holes are well aligned and check before welding if you still have a matching pair. You can see two red marks on the last photo, so this was my second flange pair. I marked the other flange pairs with 1, 3 and 4 red marks.

In the previous step I mentioned that I drilled holes.

I had to drill more holes in this project:
- Holes to be able to mount the casters.
- Large holes for the M16 bolts and the slots.
- Large holes to bolt the engine to the central section.
- Large hole for the lever to tilt the central section.

I marked the holes and used a drill press for most holes. First I drilled a small pilot hole and increased the size of the drill bit after that. For the large holes I used a hole saw.

I cut a piece of steel plate which was a bit larger than the mounting plate of the casters. Then I marked where the holes had to come and drilled the holes.

I cut 4 short pieces of square tubing and 8 small square pieces of steel that were slightly smaller than 2x2 inches and I welded those small pieces on the ends to close them. It is not really needed to do this but I think it looks better and it protects the inside from rusting.

Then I welded the 4 plates with holes to the 4 short pieces of square tubing and used the nuts and bolts to test if the casters fitted there.

This part is built from a steel plate which is 10 mm (3/8") thick. It is probably a bit overdone but I wanted this part to be strong since it has to carry the weight of the entire engine.

I first made the end of the slots by drilling a pilot hole and after that made the hole larger with a hole saw. Then I used an angle grinder to remove the middle section of the slots.

The slots had to be wide enough for the bolts that I used to bolt the central section of the engine stand onto this part. I used M16 bolts so I made the slots 18 mm wide.

The distance between both slots had to be large enough for the pipe that will be used for the rotation. (See next step.)

On the top and bottom of each plate I welded a small plate with a hole inside and I welded a nut to that hole. Then I cut 4 pieces of M16 threaded rod of 25 cm (10 inches) long and added two nuts tightly screwed together so this can be used as a long bolt.

I added 4 photos of the mechanism when it was ready. On the two photos where the steel is not yet painted, the central section was tilted 90 degrees so then it was halfway through the rotation. On the two photos where the steel is painted you see the normal position of the mechanism.

The mechanism for rotation is connected to the mechanism for height adjustment.

I welded a 2" pipe to the backside of the plate for height adjustment. I did not place the pipe in the middle but closer to the top of the plate. That way I had more length for height adjustment in one direction than in the other direction. In one direction I can lower the height by 5 cm (2") and in the other direction I can raise the height by 15 cm (6"). And when I rotate the center section without the engine present the height adjustment also changes, so then I can lower the height by 15 cm and raise it by 5 cm. This gives me a total of 30 cm (12") where I can adjust the height.

Height adjustment is handy to get an ergonomic working height, but it is mainly intended to get the center of gravity of the engine aligned with the rotation axis. Then the engine is perfectly balanced when it is being tilted and flipped upside down. It only takes 2 fingers to tilt the entire engine and it can stop in each position and does not fall back.

Tilting is possible because the 2" pipe can rotate in it's brackets. On each side of the vertical frame I welded a steel bracket. These brackets are used in piping systems in factories to clamp pipes to pipe bridges. I used another bracket on top of the pipe so each pipe is loosely clamped between two brackets and held in place while it is still possible to rotate the pipe and therefore the entire engine.

When I tighten the bolts on the brackets the pipe is clamped down firmly and then the rotation is no longer possible. That can be useful during the work on the engine.

We mainly used the engine stand with the bolts of the brackets partly tightened. Then the engine felt very stable when working on it, but with some force the engine could still be flipped upside down without loosening the bolts in the brackets. To get some leverage I drilled a large hole in on of the 2" pipes and pierced a small pipe through this hole. The small pipe can be used as a handle to flip the engine upside down. I found this small pipe while it already had a thread cut on the end so I could easily screw on a cap. That cap keeps the small pipe from dropping out of the hole but it can still easily be dismantled. On the other end of the pipe I welded a plate that was larger than the hole so the pipe cannot fall out at that end either.

After construction I transported the engine stand to the guy who asked me to build it. He wanted to be able to use the engine stand immediately and he did not want to wait for me to paint the individual parts, because it would take some time for the paint to fully dry.

So when I arrived with the engine stand we immediately assembled the engine stand and we mounted the engine. On the first photo you can see that the engine is already in the stand but it is not yet painted. We first tested the stand and then I painted it with the engine in the stand. You can see that on the second photo which was taken on the same day. When the project was ready and the engine was back in the car, the stand still had a few areas which are not painted.

Are you now wondering why the classic car in the background of the first photo is blue while the Bentley is green? The blue car is a Talbot which is also being restored in the same garage but I was not involved in that restoration.

After several months of work the Bentley is now ready so the engine stand is not needed at the moment. But more restoration projects are coming, so for sure the engine stand will be used again in the future.