engine mount nightmare

[Rhylsailer99]

My bukh engine fitted to a cobra 850 i noticed the 2 front mounts loose so tried to tighten the nut and it just spins, im guessing a water pump leak as dripped water over many years into the mount area.
i went to drill them out to pour epoxy in as a quick fix for now but on one side the drill bit snapped inside ouch .
I think this winter i will have to remove the flywheel to get access and another big job broke out. the mounts look like they been bodged before as both have an extra bolt screwed in the front so 3 bolts total for each of the front mounts.

 

[Plum]

My bukh engine fitted to a cobra 850 i noticed the 2 front mounts loose so tried to tighten the nut and it just spins, im guessing a water pump leak as dripped water over many years into the mount area.
i went to drill them out to pour epoxy in as a quick fix for now but on one side the drill bit snapped inside ouch .
I think this winter i will have to remove the flywheel to get access and another big job broke out. the mounts look like they been bodged before as both have an extra bolt screwed in the front so 3 bolts total for each of the front mounts.

Oh dear. Sorry to hear of your problem. Can't visualise from your text the arrangement of the nut that spins and the bolts you are trying to drill out. Can you post a picture then hopefully you will get some suggestions, hopefully some that avoid removing the flywheel.

Www.solocoastalsailing.co.uk

 

[Rhylsailer99]

Oh dear. Sorry to hear of your problem. Can't visualise from your text the arrangement of the nut that spins and the bolts you are trying to drill out. Can you post a picture then hopefully you will get some suggestions, hopefully some that avoid removing the flywheel.

Www.solocoastalsailing.co.uk

will do I'm popping over 6am to hopefully get 2 screws in place to hold until winter

 

[vic008]

No prob removing flywheel. Be sure to torque up after.

 

[Rhylsailer99]

Pics of engine mounts bukh dv20

 

[Rhylsailer99]

After oversize drilling one and then filling with thickened epoxy I have a 6mm coachscrew 60mm long gripped in well. The other side was budged as I wanted to get out and has held well after 8hrs on the motor. The engine only really rocks during start up and once running sits very still.

 

[Refueler]

I know your pain .....

My Perkins 4-99 in my boat was mounted using inadequate mounts to heavy hard wood beams. After 25 odd years - when I bought the boat and started to use the throttle more ... ended up with mounts failing.

The horror story began.

The hard wood beams had the bolts put in from underneath, meaning that to replace meant lifting out engine and beams as one. The bolts only had about 1cm gap to bilge !! Not so easy when engine bay is only just slightly bigger than the engine itself. I had the Yard Diesel guy do the job ... and it meant cutting and dismantling the 'furniture' around the companionway.
When he finally had it all out .... it was plain that we had mini Petter mounts fitted for a 40hp engine !

First was to get rid of the wood beams ..... so good strong angle iron beds were put in - this also meant mount bolts could be worked top and bottom.

The work proved beneficial not only then - but also later when the engine seized and was replaced with the present 4-107. A straight lift out - drop in job.

 

[jamie N]

I'm not sure whether this might be good news or not, but your engine is probably in the region of being a 10hp unit, which would normally be giving a maximum of 100kgs. of forward thrust, which is 25kgs. of 'shear' force per bolt, which is the equivalent of hanging a suitcase from each bolt.
All the above are very flexible generalities to give rough ideas of the forces involved; not a lot.