This is my v drive set up. I'm not convinced it's a good way to do things. The Walter company had a fit when I showed them the pillar bearing. There's no wiggle room at all not having a u joint. Is there anybody out there that can give me advise if I she keep the set up or change it out. Of course Walter wants me to buy a jack shaft from them. I'm already spending $2600 on a total v drive rebuild. What should I do?
It looks like you boat was repowered recently. Since your new gearbox appears to have an offset, there is no telling from a picture what state of alignment the V-drive was in before you removed it. With the repower it is unknown from pictures if you can even physically ever achieve v-drive input shaft alignment within the +/- 1.5 degrees that Walter Machine specifies.
If you have not removed the V-drive you need to measure and calculate the misalignment using trigonometry. If you have removed the V drive before checking the alignment that was a mistake. Sending it to Walter Machine before understanding the depth of your problems may have also been mistake.
I say this because of the repower you may actually have the wrong V drive and wrong V drive gear ratio. If your new gearbox is not 1:1 you cannot run the stock a 2:1 RV-10. You will need a 1:1 RV20 or RV26 to handle the 2x tourque. Most twin-disc type design boxes are 2:1. At 4:1 you also will never be able to prop your boat correctly.
I understand the use of the pillow block. On paper and in a perfect world OK, but in practicality the job calls for a U-joint at the gear box flange.
It took me years for to fix the problems introduced by the previous owners repower job on my boat.
Pete, So you think I should have a local machine shop to install a U-joint at the gear box ? The gear box is an RV-10 (1988 ). The engine is a Perkins 4108, original I think. There's nothing in the paperwork stating a repower with a different engine. I just dont know where to go from here. This whole thing caught me by complete surprise.
Picture of the gearbox (blue thing) looks like a Hurth of some kind. Questions: What model gearbox and what is the gear ratio.
So you have an RV-10 V-drive. I assume its 2:1.
So sounds like you were repowered with a Perkins 4-108. They are painted blue and come with a Hurth. The preferred gearbox is the Borg Warner Velvet Drive 71C. Its direct drive so the ration is 1:1. The output is not offset from the crankshaft centerline. With that, the rebuilt 2:1 RV-10 and the proper telescopic drive shaft you will back to normal.
Your other option, since you are essentially buying a new V-drive ($2600 is twice what you pay for a used V-drive) you can look for a 1:1 RV20 or 26 and a telescopic shaft. You keep the 2:1 Hurth. There folks on this site that have gone that way. It seems to work.
pete, are you able to rebuild these v drives? Walter Co. seems a little busy and they wont talk to me about my problems. I didnt know you rebuilt these things. I sent you a message with my phone number. Can you please call me?
In response to your request for a V-drive in the Chandlery.
I saw you pictures and they don't show the V-drive but the V-drive does not have a flange. It's a 1"dia shaft with 10 teeth that plugs into the hole. Gearbox flanges vary. Some are 3 bolt others are 4 bolt with different hole patterns. That's the end where the U-joint goes. I bought my gearbox 4 bolt velvet drive flange and U-joint on Amazon. Spicer makes all that drive train stuff. The section of 1" 10T shaft I got on Craigs list but I'm sure a marine machine shop can supply the shaft material to your specifications. I'd say your chances of finding a used original telescopic shaft assembly are close to zero so you will need to improvise.
http://www.pearson365.com/forum/index.php?topic=1268.msg6839#msg6839
What V drive gear ratio do you need? I'm thinking 1:1 since I'm pretty sure you have a 2:1 Hurth in there. Pete
This is the other flange that sticks into the V drive. I could just connect it back up and try to get a local machine shop to make a U-joint for one of the ends. I'm at a total loss what to do. It has been modified and prolly ruined. I dispirately need to fix this in the next 2 months.
Its doesn't look that bad. You need to flush that rusty oil out of there before it becomes a total loss. Remove the top and bottom covers and flush it out with safety clean. Examine the gears. If they are pitted you will need a new gear set at a minimum. If there is heavy rust it's probably scrap. If it still turns smoothly it may still be salvageable.
Still confused by what I'm seeing in your disassembled picture. I don't see the cover and oil seal. Part# 24
I already sent the whole thing to Walter. I took the covers off and it was a mess. There was lots of pitting everywhere. Walter called me back and said it was a total basket case. I would prolly have to agree. I found a survey done on the boat over 10 yrs ago and the surveyor found water in the oil then too. I'm not excited about the $2500 rebuild cost they want. Plus, my boat has that solid shaft without a U-joint and a pillar bearing. Its not designed to OEM specs, its suspect at best. I may need another jack shaft too. I hope to find another RV-10 and jack shaft, or install a U-joint at one end . I just dont know how to progress forward. I dont have any contacts to find parts either. Its pretty frustrating.
My RV10 just has a flange like this. Kinda weird.
That's a normal unmolested RV-10. It has a self aligning bearing that allows up to 3 degrees of misalignment up, down left right.
What is we thought out of the box a bit? If I was in your position with the few options that appear to be out there, I would direct couple a hydraulic pump to the engine and a hydraulic motor to the prop shaft. For inspiration, look at all the agriculture and construction equipment out there with the same type of setup. Mowers, snowblowers, rotary brooms and on and on. Equipment should be easy to acquire new and more so used.
Forward/Neutral/Reverse would be accomplished with a simple 4 way valve. The valve actuation could be cable operated from the pedestal. If the prop should wrap up with something, the safety relief would provide a fail safe, something you don't have now. Hoses would connect the pump to the hydraulic motor. No gear box, no driveshaft, no gear ratio concerns, no alignment... simple and safe.
A simple heat exchanger would be required to dissipate the heat in the hydraulic system. Once you have the hydraulic system installed, a set of hoses could also operate a hydraulic windlass, bow thruster, davits or perhaps a furler.
In the late 78's F&C utilized a hydraulic drive for the prop and mounted the engine 90 degrees to the keel line to save space.
Dale
Actually the entire photo got cut off on the right side. You cant see the flange just outside the picture. The custom shaft bolts on to the flange and goes directly up to the tranny, no U-joint anywhere. I talked to another guy in Chicago today and when I told him I had a Hurth bolted up to a perkins, he immediately said my transmission out shaft is 2.5 inched below the engine shaft. That would explain the need to go with a small 1 1/8 " shaft and not the original jack shaft. If I try to go back with the original jack shaft, it wont fit. This is getting very complicated. Heck, I might need to go with the hydraulic option. Might not be such a bad idea after all.
If hydraulic pump & motor is employed would there have to be an oil cooler in the loop?
It would seem like an oil cooler would be needed. I dont know if there is an oil cooler on the perkins. I may need to cut that stringer in half and place the new jack shaft in there. Then build a bridge over the new jack shaft for support.
I like what Dales thinking and initially I also think that a hydraulic drive train seems like a cool idea. I looked into it, ran some numbers and got specs on some pumps and motors. Figuring that we have 40 HP to play with proved to get out of hand very fast. Approximates to about a 4 cu in pump running at 2000 RPM to deliver 35 GPM at 3000 PSI.
Efficiency is perhaps the biggest drawback. Singe you can't use piston pumps which are the most efficient (noisy and short lived) you may want the smoother operating vane pumps. So your efficiency will be about 60% max. So you are going to need a huge hydraulic heat exchanger. I am also not convinced that you will also need gear reduction on the pump and possibly you will need to retain your Walter V drive 2:1 reduction ratio to reduce the tourque spec on the hydraulic motor.
This article sums it up pretty well. https://www.sbmar.com/articles/some-tips-experiences-on-hydraulically-driven-sailboats/
As the article states , if you boat is already designed to have a conventional mechanical drive train, you would be crazy to consider hydraulic drive as an alternative for a cruising boat drive train that requires continuous duty.
Pete
Prolly the best bet would be to just install another drive shaft. Can I get a specially made telescoping drive shaft at a car drive train shop? I hate to ask the price of one at Walter Co. I'm thinking thousands......
Just throwing this out for giggles but shafts for tractor PTO's are telescoping AND have u-joints at both ends. Remove one of the u-joints, add a coupler for the transmission connection and there you are. These PTO shafts are designed to handle heavy torque and are rated for various horsepowers. eBay has pages & pages of them.