rebuilding engine

[vicsponjr]

Re: rebuilding engine

The short block marine engine would be the same, except for brass freeze plugs, and maybe a bigger cam. Changing freeze plugs is easy.

 

[man-of-war]

Re: rebuilding engine

went this morning to see the michanic,he said he will give a 30 days guarentee on the rebuild,i told him that i wanted a 60 hours guarentee from the clock houres thing on the boat's dash,he said thats ok. the stupid thing is, looking for a block and he had 5 at his shop.he said there is a demand for these blocks price ranges from 500 to 1500.to sleeve a cylinder normaly takes around 45 min, he said when he does it it takes 4hours to do it right.ill take his word for it.i also told him to use the hydrolic lifters not the solid ones.is there a changeable spring in the oil pump to make the oil pressour higher?on the 13th the engine is going to a dino to break it in and to tune it,/get rid of the gas in crankcase probleb .im sure that what caused the piston to defragment .when they dyno this engine do i have to take my coil and thunder bolt IV? THANKS all for the advice and help.

 

[rbezdon]

Re: rebuilding engine

A dyno test is a running test. I am sure you will have to have a complete running engine including the ignition system, otherwise how is the engine going to run?? Good decision on the lifters. For an automotive performance engine where you race and love to do maintenance, solid lifters are a good choice. On a pleasure boat where you dont want to be out there after every other run adjusting the thing, stick with the hydrolics.

 

[lowshovel1]

Re: rebuilding engine

I use solids in my bike---only 4 push rods to adjust,not to bad. would'nt even consider installing in a boat engine---maybe a hipower drag engine.

 

[man-of-war]

Re: rebuilding engine

went to see how the rebuilding was going today.they sleeved the block and did the magnitise test looking for minor cracksbefor the started to rebuild the engine. they found another hole the size of a penney. that block is toast,my question is, is a 4 bolt main bearing block beter than a 2 bolt main bearing ? the mechanic has a 4 bolt block and my block is a 2 boltmain...thanks

 

[rbezdon]

Re: rebuilding engine

4 bolt is better in the sense that the main bearing caps are mounted with 4 bolts instead of two. This is for bigger loads and is more common for heavy duty (truck) engines. If the shop is willing to give you this block for the same price as the 2 bolt, take it. It is a heavier duty engine. I did the same for my 350 when I swapped, put in the 4 boly. Actually I was surprised not to find the 4 bolt mains in all the marine applications with all the talk of how moch heavier and more severe the loads aree in a marine application. Guess the generally lower RPM range helps, marine engines all seem to top out at uder 6K when most cars/trucks red line at 6000 or more.

 

[man-of-war]

Re: rebuilding engine

thanks on the heads up on the 4 bolt.this engine goes 5000 RPM max which is around 56mph depending on the trim setting i set.....thanks

 

[rbezdon]

Re: rebuilding engine

Man of War, if thats true I think 5000 rpm is a bit over the WOT recommended rpm for that engine. When you get it all back together you should experiment with your porp size. I bet you could go up in pitch one size, drop the rpm to 4600 or so and pich up 2 or 3 mph and be running in the "safe" recommended rpm range.

 

[man-of-war]

Re: rebuilding engine

thanks again vatter41,befor all these problems came up with gas in the oil,I was on that track trying difrent props .i have a 4 blade 22 pitch prop which was pitched one size up and cupt,i also tried a 3 blade 25 pitch marag.the marag gave 38mph at 3200rpm....and the 4 blade gave 33.7mph at 3200rpm. im looking for a used 25 marag prop cant get my hands on one yet.iv owned this boat for 2 summers and only went to wot around 4 times 35 or 40 mph is fast for me.but its good to know that i have a little punch under the hood