Help required Re Replacing engine question

[jason_k]

"Hi all,
I am new to

"Hi all,
I am new to the motorboat scene,and havent started out very well.
I recently bought my first boat,a 2850 Regal 1998 with a 7.4 v8 Volvo engine (I think a L29) and duoprop ,she has 550 hours on the clock ,on our 3rd outing the engine made a load banging sound on our return ,turns out the conrod is bent.
I am being told the entire engine should be replaced for reliability and future value reasons.
I am a little tight on cash at the moment,and was told to change the complete engine,which I am finding hard to source.I would be very grateful if i could get some advice on the best options i should take .

1) replace the complete engine ,top to bottom.

2) replace the long block @ 4,500 dollars and add new pumps, altenator, etc to it.

3)Get the engine rebuilt with new conrod and other parts.

4)Or replace the 7.4 with a 5.7 gxi or the new 8.1 which i really cannot afford .

I live in Ireland , so freight will be another issue.

Any help would be very much appreciated

Thanks

Jason"

 

[el_pescador]

"I think you have answered you

"I think you have answered your own question. Being tight on cash means to me that options 1 and 4 are out of the question. Option 3 may the cheapest one (subject to the crankshaft and the block being either in good condition or repairable). And in option 2, you normally can re-use your exisiting alternator, starter, distributor, etc.

At the end of the day, either of the two options will work, so I do not understand why do you think you should change the whole engine. To me, a rebuilt engine is or can be as reliable as a new unit. If I was in your shoes, I would first try option 3, and if that does not work, then go to option 2 but reusing most of the current engine components.

The other important thing to keep in mind is that you must find out what caused the bent rod. If it was water in the cylinder, you must find the source of the water ingress and eliminate it if you don't want it to reoccur."

 

[jason_k]

"Hi ,
Thanks for the e-m

"Hi ,
Thanks for the e-mail.I agree with you , I was planning to go with option 3 myself ,that is until i was told by 2 other people in the industry that the engine would never be the same again, it will never run quite right,I will never be able to drive the boat in a spirited fashion ,followed by the high probability of the engine breaking again and essentially throwing my money away.......frustrating when you are learning about this for the first time.

Option 2 appeals to me based on the guaranteed new block,only thing I have been told is the labour of stripping down the old engine and rebuilding the new one will cost me most likely just as much as a new engine ,then I was thinking would it be a better idea to go with option 2 ,and then rebuild the current broken engine to sell it after the new long block is built and fitted , this may recoup some of the cost incurred in the new longblock.
I think option 2 may be the one for me.I get the impression that none of the mechanics want the hassle or work of stripping down the engine.they would much prefer a new engine in and old one out.

In relation to the reason why the rod went , When it happened , I opened the transom to look into the engine and seen the bottom half of the engine spraying out water into the bilge at a farly intense rate ,water level was about 12" deep just under the sump ,it was coming from one of the seams below the pulleys but above the sump, I reckoned this is what may have caused the issue in the first place,following removing all the water I found that 2 of the engine mounting bolts were sheared ,posibbley causing i thought extra strain on the crank and in turn one of the rods with the engine sitting at an angle, the honest answer at the moment is the mechanic told me it was a bent rod by the sound of it only, no compression test has been done it was purely diagnosed from clattering sound and lack of power when the revs were increased, I have asked for a compression test to be done asap, boat has been off the water now 6 weeks.

Many thanks for your help it is very much appreciated, hopefully I can return the favour sometime.

Kind regards
Jason"