Hey I have a stuck raw water pump with three broken bolts. Is there anyway to get this thing off to replace with a new one? One bolt is sheered off and there are broken extractor bolts in there too. It's a mess! Engine is a yanmar 1gm10

I'm thinking of cutting it off like this picture. Is that crazy?

Cutting off still leaves you with broken studs and a water pump housing the cannot be salvaged if need. Yes crazy!

Here is the service manual
www.jeanneau-owners.com/Manuals/3GM%20Engine%20Service%20Manual.pdf

Here is the parts list with exploded view of parts.
www.lsm-diesel.dk/2012/yanmar/pdf/motordele_1gm10.pdf

You will need to remove the front gear casing (refer Fig 2 in parts list).
The waterpump will come off with the casing.
Then you can work on it properly on a bench.
Drill out bolts and have stainless helicoils fitted.
Don't bother ordering gaskets (water pump and gearcase to crankcase.)
You will wait forever for them to arrive and pay to much.
Buy the correct thickness of gasket material, a couple of wad punches and make your own gaskets.

Have fun learning about your engine.

P.S. Drain oil before removing gearcase cover.

Gary

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garymalmgren said..
Cutting off still leaves you with broken studs and a water pump housing the cannot be salvaged if need. Yes crazy!

Here is the service manual
www.jeanneau-owners.com/Manuals/3GM%20Engine%20Service%20Manual.pdf

Here is the parts list with exploded view of parts.
www.lsm-diesel.dk/2012/yanmar/pdf/motordele_1gm10.pdf

You will need to remove the front gear casing (refer Fig 2 in parts list).
The waterpump will come off with the casing.
Then you can work on it properly on a bench.
Drill out bolts and have stainless helicoils fitted.
Don't bother ordering gaskets (water pump and gearcase to crankcase.)
You will wait forever for them to arrive and pay to much.
Buy the correct thickness of gasket material, a couple of wad punches and make your own gaskets.

Have fun learning about your engine.

P.S. Drain oil before removing gearcase cover.

Gary

Thanks Gary this is perfect! I'll give this a go this weekend.

SLOWLY!!!
Parts into separate buckets.
Plenty of before photos to assist reassembly.
NO using a screwdriver between the alloy gearcase and cast iron crankcase.
I make a card board template of the removed part, punch holes for bolts to speed up reassemble
If they are of differing lengths this helps a lot.



Clean all parts before reassemble. Wire brush all threads. Apply anti seize for obvious reasons.
As I said, have fun getting ti\o know your engine.

gary

It sounds like you're just wanting to use an extractor bit to pull out the bolts with broken off heads.
Basically involves drilling a hole through the centre of the sheared off bolt then screwing the extractor-bit into that hole until it's binds in. Then reverse turning the bit out (along with the broken bolt out of its thread).

If I've got the link right, this youtube video demonstrates this.



You just need to be carefully with your drilling (bit size selected, centred and drilled straight) so as no to damage the thread in your engine block.
If the thread in the block itself does get damaged it's not the end of the world. A last resort at that point would be to drill it out and tap in a new hole to take a slightly bigger diameter bolt than was originally is place.

Good luck with the extractor bits I've tried many times over the years it is possible but the reason the bolt usually sheers is it is seized in the tread, so the option then is to drill out the broken bolt all well and good in a drill press, free hand takes as much luck as skill. If you can get some heat in there like oxy or maybe a propane torch then douse it with water it will help and if there's enough broken bolt protruding to weld some thing to it that gives a good chance of success. Fingers crossed

Most times easyouts won't work on a boat as the bolts or studs are corroded in so tight when you try to back them out with the easyout tool it just spreads the bolt or stud as it tries to wind itself in jamming it even tighter in the hole till the easyout snaps off. The judicious application of heat in most circumstance works much better in breaking the bond between bolt and hole.

Maybe try to soak with some oxalic acid to help dissolve the rust. Then apply heat.

Hi Westimo
Had a good look at your photo.
Here it is oriented correctly.


The red is a missing or broken bolt for gearcase cover to crankcase.
The blue is a broken bolt for water pump body to gearcase cover
The greens are broken bolts for water pump cover to water pump body.

To fix the red and to do the job properly you will have to remove the engine.
Earlier suggestions of using Easiiouts will not work on such corroded broken bolts.
You have " Green" steel bolts broken off in soft bronze.
"Blue" steel bolt broken off in alloy gearcase cover
"Red" steel bolt broken of in cast iron.
This can only be repaired properly on a nice clean bench.
You will not get away with a hand held drill as per the set up video.
You have to use a drill press to control the drilling process.
You need to drill out and if you can re-tap (the same size).
If not helicoils are the answer.

To remove engine you need to take off everything you can in situ, (alternator and brackets, exhaust manifold, inlet manifold, starter motor etc.)
This will make the engine lighter and easier to handle.
lucky you have a small manageable engine!

gary

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garymalmgren said..
SLOWLY!!!
Parts into separate buckets.
Plenty of before photos to assist reassembly.
NO using a screwdriver between the alloy gearcase and cast iron crankcase.
I make a card board template of the removed part, punch holes for bolts to speed up reassemble
If they are of differing lengths this helps a lot.



Clean all parts before reassemble. Wire brush all threads. Apply anti seize for obvious reasons.
As I said, have fun getting ti\o know your engine.

gary

That's a great idea!

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LooseChange said..
Most times easyouts won't work on a boat as the bolts or studs are corroded in so tight when you try to back them out with the easyout tool it just spreads the bolt or stud as it tries to wind itself in jamming it even tighter in the hole till the easyout snaps off. The judicious application of heat in most circumstance works much better in breaking the bond between bolt and hole.

That's exactly right,, Drive in type spline extractors are another that are often a better choice than the easy out but still, their application is limited. I usually go straight to the welder and build up the top of the stud/ bolt, tack by tack and peen the glowing tack with a hammer and punch each time until i have enough build up to weld a nut on. The combination of the heat and the peening usually is enough to free the thread but real stubborn threads may require carefully working back and forth ,, and maybe a few attempts. My choice of weld rod is an alloy like a sandvik 299 or a "Weld All". These are often the type used for buttering hard facing or welding two dissimilar metals but a stainless 308 or a general purpose is better than nothing.
If you have to drill it out, make a guide if you can to keep the drill from wondering and if you have broken extractors and drill bits to get through, a re sharpened masonry bit or a carbide bit may do the job

Jolene, Great advise on choice of welding rod, I guess the idea of a hard facing rod is the ability to leave build up, which gives something to try and get hold of and reshaping or sharpening a masonry bit to try to drill old extractors is gold !

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woko said..
Jolene, Great advise on choice of welding rod, I guess the idea of a hard facing rod is the ability to leave build up, which gives something to try and get hold of and reshaping or sharpening a masonry bit to try to drill old extractors is gold !

If you use an masonry bit and re grind it, don't put too much positive rake on it. You need to leave material behind the cutting edge to keep strength in it . Don't give the drill bit an excuse to grab. A way of cheating which also works good on brass is to dull one of the cutting edges or lands. Doing this controls the depth of cut per rev and stops the drill bit trying to aggressively pull its self through,,, the downside to this is that it generates heat and if you are using a masonry bit you need to keep it very cool so you don't melt the solder that holds the tungsten in place.
keep heaps of water on it and use a good quality drill bit.
With the welding rods. the buttering electrodes are used like a primer is for paint. Sometimes, if you hard face straight onto a parent material. the hardface can tear or crack away so you lay down a buttering layer first of a special alloy. I don't use hard face to build up the broken stud just the "weld all" or the 299 (butter). 350 hard face would work but just remember that you may have to drill it out.
Low hydrogen rods are good and strong too but very hard to stop and start with ,,but i have used them to weld the nut on.
.