Mahe 36: Engines

[Cotemar]

Originally Posted by Seastream

It makes no mention regarding the threading I see on the pump shaft engine facing side.

The thread on the pump shaft is for the bolt an washer that hold the gear on the shaft.

[Seastream]

Got it, tnx. Found below pix in part B of the manual:

[Seastream]

Mahes: I spent two hours today trying to remove/replace my port seawater pump and am about to throw in the towel. I don't know how Jef (Miss Poes?) did it without removing the engine mount. In my case, the bolt in question (nearest the engine block at bottom) can only be backed out so far before it contacts the engine mount, then can't be moved further. He has hull 88, I have 91 so I'd think our Volvo D1-20 engines are the same. I'd pull the engine mount (if I could figure how to support the engine) but fear damage by disturbing the engine/transmission/saildrive alignment. I'd rebuild the pump in place but there's barely space for shrimp in front of the engine. Sheesh.

[Seastream]

Addendum: Once I've resolved this situation, I've considered replacing the two 'machine screws' closest to the engine block with a smaller diameter bolt/nut/washer assembly, with the bolthead at the front of the engine, to facilitate future removal. Thoughts?

[Seastream]

Got the pump out! Now to transfer the gear from the old pump to the new. How have those of you that have changed the entire pump held the pump shaft from moving so you could remove/replace the gear and nut assembly?

[oranaman]

Originally Posted by Seastream

Addendum: Once I've resolved this situation, I've considered replacing the two 'machine screws' closest to the engine block with a smaller diameter bolt/nut/washer assembly, with the bolthead at the front of the engine, to facilitate future removal. Thoughts?

At the beginning of the season I thought I would check the raw water cooling rate on my VP D2-40 engines very carefully - after 6 seasons use I have had no problems so far. Starboard engine 12litres/min, the port 5 litres/min. Spend a couple of days checking everything else. It had to be either the sail drive intake or the pump. Decided to try the pump first as I thought it would be easier to swap the pumps around then re-plumbing the raw water supply. In trying to do this I found that both water pumps needed the seals changing. Now this seems a common problem on these D2/D1 engines. Why do these pump seals last less than 800 hours, thats only 20000 miles in a car. Water pumps on cars last much longer.

Yes removing the water pump seems simple enough in theory until you try. On the D2-40 engine, VP have just added a "box" which contains the water pump "gears into the engine drive". The 4 bolts that hold the pump onto the box are threaded into welded on external nuts. As the bolt is 10mm longer some of the bolt's thread is exposed. I removed the port pump no problem. However the starboard pump bolts would not undo. This was because they were totally corroded. To cut a long story short I managed to removed 2 okay. The third bolt sheared. I was careful using a 1/4 socket drive and I don't believe I could have removed it. I then spend several hours cutting the welded nut off in a very confined space using every tool imaginable. Once done I have replaced it with a SS bolt and nyloc nut. After that I gave up trying to remove the pump. The fourth bolt I have left to the end of the season.

TIP - grease the ends of all these bolts to keep the corrision at bay.

Fortunately the problem was the sail drive water supply. I rigged a raw water feed from the port rear head intake and now I get 12 lites/min.
As the boat was in the water I couldn't check the stop cock. Last year I helped a fellow cruiser remove the VP saildrive in order to change the large main water rubber seal. In doing so the saildrive is split into two and we found a large marine growth, bigger than the raw water supply passages beginning to block the water supply. So it is important to visibly check the water passages in the saildrive whilst it is apart. This issue has not been mentioned in any of the articles I have read which explain how to change this seal.

[Jef & Marin, Netherlands]

Seastream,
To remove the nut you need to either hold the shaft or hold the gear.
I blocked the gear, but I do n ot remember exactly how.
There are some option:
- Use very big pliers, use strong thin strips of wood between the beaks of the pliers and the gear teeth. I used old fashioned wooden pegs, split in two.
- Use a good old filter remover, use car or motor cycle inner tyre or similar pieces of rubber between the tool and the teeth of the gear.
- Alternatively, you can use a VERY BIG screwdriver on the slot in the front of the shaft of the pump. But you should really take care that the screwdriver touches only where it does not deformn the shaft at the edges, otherwise you will damage the seals when you shift them over this part of the shaft.
With a new pump this is obviously not the preferred method.

If you have the nut off (hard due to the loctite thread lock) you need to remove the remaining thread lock with a sharp pointed tool and a small hammer.
Then you need a 2- or 3-leg puller to pull the gear of the conical pump shaft. Obviously taking care not to damage the thread on the pump shaft, for instance by keeping the nut on the thread of the pump shaft.

Good workmanship is the ability to apply huge force without causing damage..... Is this the correct way to say this in English?

[Seastream]

Jef: Thanks for the response. I did use pliers, rubber strips and socket wrench but once I realized I'd need a gear puller to take the gear off the shaft I took the pumps to the marina shop and asked them to swap the gear over to the new pump. Can you (or anyone else here) recommend a part number and source to purchase an appropriate size gear puller so I can do this when my starboard seawater pump fails?

[Seastream]

Regarding cleaning the primary fuel filter and replacing the secondary filter: Is there any pressure to be relieved from the system or do I just shut off the fuel at the tank, then unscrew the primary filters for cleaning (filling bowls with fuel before reinstalling) and replace the secondary filters? After that do I just prime the system at the engine via the manual fuel pump, bleeding via a partially unscrewed bleed screw?

[DotDun]

Originally Posted by Seastream

Regarding cleaning the primary fuel filter and replacing the secondary filter: Is there any pressure to be relieved from the system or do I just shut off the fuel at the tank, then unscrew the primary filters for cleaning (filling bowls with fuel before reinstalling) and replace the secondary filters? After that do I just prime the system at the engine via the manual fuel pump, bleeding via a partially unscrewed bleed screw?

No pressure in the system.

Fill the filter bowls, I've never had to prime. A little air will work itself out.

[Seastream]

Got it, tnx. Another Q: What's the ID of the fuel hoses that pass thru the primary water/fuel separators/filters? I tried looking on the hoses but couldn't get a good look due to their location. I want to purchase 'barrel' barbs so that in an emergency I could bypass the primary filters. The secondary (on engine) filters would protect the engine in such a case.

[EricHol]

The Document of the whole process is to big to post here (Lots of Pictures), so send me a private e-mail and I can send you a copy.

Dear Mark,

This winter I have to change the air filter and spotted your solution. Is the document your reffering to still available? Would help me a lot, thanks.

Brs Eric

[Seastream]

All:

I have Volvo D1-20 engines. I ran aground today in the ICW in GA. Must have sucked lots of sand thru the seawater intake getting loose as the engine exhausts were steaming (even at 2000 rpm) afterwards. On closer inspection, this clearly destroyed the seawater pump impellers as I found most of the impeller vanes jammed at the inlet of the starboard heat exchanger. Q: Can I remove the inlet/outlet plates (held by three hex head bolts) on the heat exchanger to better see/clean it, or will this unleash springs, ball bearings, flying monkeys, etc.? I'm stuck in Brunswick, GA whilst I source impellers, then r/r the pumps. Ironically, I performed this process before we left NH in October.

[Seastream]

All set with the heat exchanger. Another Q: Where on the engine are the engine zincs (if any) located?

[Edmund]

The Volvo D1's have no internal engine zink, only on the propeller and drive.

The drive and the engine are electrically separated, and I've been told you should be able measure at least 600 ohms between them.