And when you add to all of the other advantages of the Oberdorfer that it doesn't require a gasket for the impeller cover plate due to the addition of an O-ring it is so much easier to service.
A story of the engine that could.... Then didn't…NOW DOES
- Thread starter jssailem
- Start date
- Oct 22, 2014
- 22,048
All the info about an "Oberdorfer pump" sounds great. I could not find a site with information about a match to the Perkins 4.108/4.107.
Here is the Sherwood G65 design drawing. Looks similar in simplicity to the design drawing of the Oberdorfer. (see attached PDF)
It is said, the devil is in the details. The Sherwood design has 4 bolt holes that attach the pump to the engine block. The pump is driven off the high pressure fuel pump shaft. That shaft is gear driven by the Engine cam shaft.
Sherwood G65
When reviewing the Oberdorfer pumps I can not find one that mounts to the 4.107 engine.
Here is the Sherwood G65 design drawing. Looks similar in simplicity to the design drawing of the Oberdorfer. (see attached PDF)
It is said, the devil is in the details. The Sherwood design has 4 bolt holes that attach the pump to the engine block. The pump is driven off the high pressure fuel pump shaft. That shaft is gear driven by the Engine cam shaft.
Sherwood G65
When reviewing the Oberdorfer pumps I can not find one that mounts to the 4.107 engine.
Kinda almost the same but very different.. In order to make it work, a new custom shaft (longer and with a male drive end.) would have to be machined then an adapter plate to mount pump to engine.(with a boss to engage the engine side seal). . I reckon that would cost $300-$400 to have that done at a good machine shop.
I rebuilt a couple of the Oberdorfers for buddies with Westerbeke engines.. we changed the bushing from carbon to oilite bronze and put an old fashioned grease cup on the bushing so we could grease the shaft by screwing the cup down a half turn or so every now and again.. We sourced the lip seals locally from Motion Industries once we had the dimensions. That was back in the day when I had access to some outstanding machinists..
I rebuilt a couple of the Oberdorfers for buddies with Westerbeke engines.. we changed the bushing from carbon to oilite bronze and put an old fashioned grease cup on the bushing so we could grease the shaft by screwing the cup down a half turn or so every now and again.. We sourced the lip seals locally from Motion Industries once we had the dimensions. That was back in the day when I had access to some outstanding machinists..
- Oct 22, 2014
- 22,048
Those were the days my friend. We thought they’d never end….
I just found out my machinist buddy is retiring. I'm not sure what I'm going to do when he sells his shop.
Thats why we old guys have to cultivate younger friends!
- Oct 22, 2014
- 22,048
Buy up his tools. Build a shop. Call it a school. Deduct the costs. Provide a non profit space for a few select young folk to learn the skills and provide you free boat parts.
That is thinking out of the box. I don't think anyone should learn machining from me though
- Oct 22, 2014
- 22,048
Yup, I tried that in business and it worked for a while, then they either got promoted or retired before I did!
Wow, I'm way late on this thread but I found it while researching my own issues. I have a CD 30 with a Westerbeke W21A that had low compression. Had the head redone. Still low compression. Stuck rings? No way to pull this engine out of the boat. Most people offer that as suggestion #1. Not happening. I'd pulled the head 3 times before so I could do it in my sleep but dropping the pan and pushing the pistons out looked tough... it wasn't. A crow bar and a little manipulation of the engine mounts got the job done. Reversed the front mounting brackets to raise the engine higher and lower.
Rings were stuck in the grooves... big time! I soaked them for 2 months prior with Deep Creep, Mystery Oil, PB Blaster... compression got worse These rings were STUCK. It took hammers, and heat and chisels to get them out. NO amount of soaking would have ever freed them up. I'm about to hone the cylinders and install the pistons with new rings. I did it all in the boat. Sometimes you just have to be creative. I'll let you know if it runs.
Rings were stuck in the grooves... big time! I soaked them for 2 months prior with Deep Creep, Mystery Oil, PB Blaster... compression got worse These rings were STUCK. It took hammers, and heat and chisels to get them out. NO amount of soaking would have ever freed them up. I'm about to hone the cylinders and install the pistons with new rings. I did it all in the boat. Sometimes you just have to be creative. I'll let you know if it runs.
Attachments
- Oct 22, 2014
- 22,048
Welcome to SBO and to the party.
I’ll be waiting to hear you got your Varooom.
It is an exciting moment.
Resolving the issue in the boat is a bit rad. Not sure that was an option. It would be like crossing between two ten story buildings on a rope with no net on my boat.
Good luck. I look forward to celebrating your success.
I’ll be waiting to hear you got your Varooom.
It is an exciting moment.
Resolving the issue in the boat is a bit rad. Not sure that was an option. It would be like crossing between two ten story buildings on a rope with no net on my boat.
Good luck. I look forward to celebrating your success.
- Oct 22, 2014
- 22,048
The SAGA continues.
At the moment I am in front of my computer attached to a big screen. I have been addressing the weather conditions in the Atlantic, as my friend David, is making a late season crossing.
I spent a 4 days last week on the boat. The Mechanic and I removed the water pump and the exhaust pipes after I showed him the issue of the exhaust pipe being too low, creating a water back flow issue. We decided to add 4 more inches of height to the exhaust pipe before the water is injected. This we expect will allow the water to flow down and out the stern.
The water pump needs a rebuild. I ordered a kit from Florida, which is scheduled to arrive tomorrow the 4th. Looking at the beginnings of corrosion on the cover plate, I decided to also order a new replacement pump. I found a source in California. It is less than a BOAT Buck and might last another 30-40 years. Was offered free shipping and would arrive on the 2nd. The box did arrive. The box was for another order. Error in the shipping room. Got on the phone. They said "SORRY". Got to work and are sending another pump to me to arrive on the 4th.
This is good, as I am planning to go to the boat on Saturday and get both the Exhaust and the Pump installed by Sunday.
Hiccups abound on this project.
At the moment I am in front of my computer attached to a big screen. I have been addressing the weather conditions in the Atlantic, as my friend David, is making a late season crossing.
I spent a 4 days last week on the boat. The Mechanic and I removed the water pump and the exhaust pipes after I showed him the issue of the exhaust pipe being too low, creating a water back flow issue. We decided to add 4 more inches of height to the exhaust pipe before the water is injected. This we expect will allow the water to flow down and out the stern.
The water pump needs a rebuild. I ordered a kit from Florida, which is scheduled to arrive tomorrow the 4th. Looking at the beginnings of corrosion on the cover plate, I decided to also order a new replacement pump. I found a source in California. It is less than a BOAT Buck and might last another 30-40 years. Was offered free shipping and would arrive on the 2nd. The box did arrive. The box was for another order. Error in the shipping room. Got on the phone. They said "SORRY". Got to work and are sending another pump to me to arrive on the 4th.
This is good, as I am planning to go to the boat on Saturday and get both the Exhaust and the Pump installed by Sunday.
Hiccups abound on this project.
Are you adding a drain plug to the low point of your exhaust so that you can drain the system down? I drain mine whenever I lay the boat up for several months. That way you can eliminate the lift back pressure from the system when needed.
Your exhaust problem is near universal. The ABYC code is poorly written on this point. The code requires a high riser at the stern just before the exhaust exits at the transom. This presumably to keep following seas from splashing into the exhaust system and flooding the engine. However, what usually occurs with this design is that the top (spill point) of the transom riser is higher than the engine exhaust outlet spill point. With a low engine idle speed the exhaust system can fill with cooling water that is never completely expelled. Upon shutting down the engine, that water washes forward and can flood the engine. That is probably what originally happened to your engine. It happened to mine. As a temporary work around every boat owner should race their engine for a second just before shutting it down to blow out the accumulated exhaust water. Raising the engine exhaust spill point is the right thing to do. The ABYC code should probably be re-written to place the riser at the engine instead of at the transom. Even with your new elevated engine exhaust spill point you should still blast the accumulated water out of your exhaust system every time you shut the engine off. Happy motoring.
@RoyS very interesting - my engine manual specifically says to raise engine RPMS to 3000 for 30 seconds and repeat prior to shutting down. I think I'll keep that procedure! For sure the high point on my transom engine exhaust is higher than my engine.
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