CD36 Perkins 4.108 Gantry Lift & Engine Bed Replacement

[John Ring]

It's time for a new engine bed on Tiara, so the old Perkins 4.108 had to come out. I rigged up a gantry using a transmission stand, an aluminum I beam (6"x4"x3/8"- six feet long), a trolley, and a ratchet hoist. The whole system worked really well.












John
CD36 Tiara

[David van den Burgh]

That's a heck of a job - and done with style. Nice.

[tjr818]

What a tight fit. Very nicely done. I do have a question though. I always thought, though I've never done it, that you could use the boom to pull an engine. I see now that your method, using the trolley, seems far superior. Thanks for sharing.

[John Ring]

Thanks Guys.

Building the gantry and lifting the engine was the fun part. Here is where the work begins; cutting the old mild steel bed off the hull with a Dremel. Here you can see where the old steel tube just crumbled away in my hand. The whole outboard side of the starboard tube is gone, to the length of the aft motor mount. There isn't much left supporting this corner of the motor. The Dremel and a #543 bit actually do a a nice job with fiberglass. Most of the old steel bed is fine, so maybe I'll just cut the lower tubes off & weld some 304 stainless tubes in their place, then set it back down on the old tracks. The old Perkins (1,300 hours) runs great, so a new motor and matching bed aren't needed.

I've seen smaller engines lifted with the boom. Not sure I'd try that with a 600lb Perkins. The smallest parts of this gantry (hoist, and the trolley) are each rated at 1,000lb capacity.

John
CD36 Tiara

[jbenagh]

John,

Awesome!!!! What did you use for a load balancer on the engine? It looked like just chain and you hit the center of gravity with your lift.

I'm wondering how I would make a similar lift work on the CD30 where the CG of then engine is very far aft of where I could locate your gantry...

Jeff

[John Ring]

I gotta say cutting the engine bed free with a Dremel was the nastiest, dirtiest, filthiest, dust choked boat job I've ever done. Glad it's done with. I ended up using the gantry again to apply upward force to the engine bed while driving wedges under the bed, even a after all the tabbing was cut away. With a few hundred pounds of pull, and a few hammer taps on a wedge, it popped free one side at a time.

With the engine bed out, I see the aft stb corner is worse than I thought. And, both lower tubes are rusted throughout on their inner sides. It looks like the engine coolant vent loop sprayed sea water back there for years before I bought the boat. There's no point in trying to save this bed - I'll have a new one made up using a more corrosion resistant material.

Jeff: The CG was aft of the lift point here too. I tried an engine leveler at first, but it took up all the lifting space above the engine and I couldn't lift enough to clear the oil pan over the bottom of the bed to move forward at all. After that, I just cut 1/4" chain to the required short lengths and shackled them onto the two lifting tabs and also around the fwd/port motor mount bracket. I set the lifting hook as far aft as possible - didn't quite hit the CG and the aft chain carried more than it's fair share of the load. This arrangement gave me a very low lift point and a solid three point base to keep it somewhat level. It worked great this way.

John

[John Ring]

I finally got around to cobbling the video together. Link: http://youtu.be/uk6uejgXHSI

If you need to lift an engine, a small gantry is a great way to go!

John
CD36 Tiara

[Skylark]

Oh my, that's just too much. Anyone interested in buying my CD36?

[K Chiswell]

I just finished that same project earlier this year. I struggled with how to rebuild it but finally decided to use G03 fiberglass board. I'm real happy with the result. Good luck with the rest of your project.