mercruiser crankshaft interchange? what year gm

[wildpeanuts]

i have a 2002 stingray with 4.3l gm. the rod started knocking and it messed up the crankshaft. checked the oil and had water in it. i think it was from the rain storm a couple days before going out. forgot to check the oil before going out.:facepalm: i was woundering what year and model gm truck to tell autozone to look up for a crankshaft.
thanks for all help
charlie

 

[NHGuy]

Re: mercruiser crankshaft interchange? what year gm

Don't buy a truck crank, get a real marine crank.
And before you reassemble that motor you should check any possible water sources. The main things to check are the cooling system which you can plug and pressurize, and the exhaust. Check the exhaust manifolds and the risers for water passing through the water jackets into the exhaust. I have been told a good way is to dry the exhaust area really well. Block off the cooling passage at one end and put water in it. Then wait to see if any shows up in the exhaust.
If you don't find the source of the water and fix it, the new crank will break too. We can't let that happen to you.

 

[Bondo]

Re: mercruiser crankshaft interchange? what year gm

i have a 2002 stingray with 4.3l gm. the rod started knocking and it messed up the crankshaft. checked the oil and had water in it. i think it was from the rain storm a couple days before going out. forgot to check the oil before going out.:facepalm: i was woundering what year and model gm truck to tell autozone to look up for a crankshaft.
thanks for all help
charlie

Ayuh,.... Welcome Aboard,... I imagine they'll laugh at ya....

Try a Machine Shop, or a GM dealer...
You'll need the numbers stamped into the deck of the block, forward starboard corner, just at the base of the head...

Don't buy a truck crank, get a real marine crank.

Ayuh,... What's the Difference,..??

 

[NHGuy]

Re: mercruiser crankshaft interchange? what year gm

Sorry, Bondo your word is law! I'm the dope who thinks cam=crank I guess.:facepalm:
Please rip me if they are the same too!

 

[wildpeanuts]

Re: mercruiser crankshaft interchange? what year gm

lol....i'm a Honda tech. i thought the different was the cams in the gm 4.3 auto engine and the marine engine. i have read you can change the crank but you cant use the cams on the 4.3L. whats the difference in the cranks?

 

[adeneo]

Re: mercruiser crankshaft interchange? what year gm

I have a bunch of Volvo P, Merc and GM S10 and Astro crankshafts lying around the shop, all from around the mid to late ninety's, and they are all exactly the same.
The same goes for regular car and marine cranks for the newer engines with vortec and balance shafts as well.
Also have a lot of camshafts, and the difference between the truck and marine cam's are minescule.

As for testing exhaust manifolds, acetone is actually better then water as it's thinner and creeps better. Sometimes a little heat is good as well, as some cracks only appear when the metal is warm and expands, just be careful not to set the acetone on fire.

 

[wildpeanuts]

Re: mercruiser crankshaft interchange? what year gm

thanks adeneo.... i didnt think there was any difference in them. some ppl say there is and some say not. i think i can get away with ememy cothing the crank and replacing the bearing on the one rod. the rod isnt scratched up or look bad. the crank was a little but not bad. after using the ememy colth the crank smoothed out. what have i got to loose. it only takes about 20min to pull the motor back out to put a crank in it and another set of bearings in it. i checked the manifolds with brake cleaner and saw no crack or seepage. the cover for the engine was not covering the engine about 8inchs while it rained hard 2 weeks before i took it to the river. didnt check the oil like u should had before i went out not thinking. got a mile from the shop and didnt have no power then started knocking...