i need some engine builder advice.

[fishingman220]

I have torn down my 96 350 mercruiser due to it being locked up, ended up being the exhaust manifold leaked water and got in the valves and rusted the pistons to the walls. well we got it tore all of the way down and i have been honing the cylinders and got them all cleaned up looking good, except one. there is a little spot that was pitted from rust, it maybe 1/16th of an inch wide and you can feel it with your finger but not with your finger nail, not very deep at all. do you think it will be ok to put back together with that? i really do not want to take and get it bored and new pistons, but i guess if i have to i will, but how much will it hurt to leave it like it is?? also, i am going to buy he rebuild kit from PAW, is there anything in there that will not work for marine??

 

[Don S]

Re: i need some engine builder advice.

As long as you haven't honed the cylinders past their limits, you should be fine with a small pitted spot.
Of course, when all the engine experts get here you will need a new block, new pistons, special rings and all the other retoric.

 

[fishingman220]

Re: i need some engine builder advice.

ok, i ran the hone in that cylinder for at most 20 seconds with the tension set about 1/2 way, i dont think i removed to much

 

[dr_bowtie]

Re: i need some engine builder advice.

as long as you put a good cross hatch in it I would say it is fine...I have re-ringed cylinders like that and had no issue...

when you hone an engine hone all cylinders the same amount of time to keep them consistent or use a bore gauge

I use tranny fluid and honing lube and make sure you wipe the cylinder clean after you hone it...you dont want the grit boring the cylinder after you fire it up...

 

[fishingman220]

Re: i need some engine builder advice.

i will do the rest the same amount, i used pb blaster as cutting oil, but i have a buddy comming over tomorrow who really knows what he is doing, i think he is bringing all he needs plus a bore gauge. thanks. is there any difference in any gaskets for putting back together in marine and automotive??? also, if i get the block dipped do i need to replace the cam bearings???

 

[Don S]

Re: i need some engine builder advice.

Yes, there are good and bad gasket sets. If you don't want OEM, a good set of Felpro gaskets should do the job nicely. They have composite head gaskets.

 

[fishingman220]

Re: i need some engine builder advice.

well paw offers a up charge to get all felpro gaskets so i guess i will get that. anything special to look for in exhaust manifolds? i found a set on ebay for $99 each new made by GLM made to mercruiser specs and has all the bosses and threaded. do you think these will be ok???

 

[dr_bowtie]

Re: i need some engine builder advice.

also, if i get the block dipped do i need to replace the cam bearings???

yes if you dip the block you will need new cam bearings...

 

[fishingman220]

Re: i need some engine builder advice.

ok thank you, and thanks for the fast response

 

[Don S]

Re: i need some engine builder advice.

Might want to do a search for a post by bondo on the GLM exhaust manifolds and risers. He had problems with the gasket surfaces between the manifold and risers not being flat and the leaked.
The cheapest way to go is seldom the best way to go.

 

[futz]

Re: i need some engine builder advice.

osko, never had a problem with thier stuff. many places have the whole shebang in one box at one price, 2 mani's
2 risers, and all the gaskets. seen the kit for 500.

Don't want to post the sites, but i think you should check this site see what price they give for the kit first.

 

[fishingman220]

Re: i need some engine builder advice.

well my risers look almost new but the manifolds looked ok, till i pulled them off and the underside and apparently the inside is rusted real bad. so all i need is the manifolds and gaskets

 

[futz]

Re: i need some engine builder advice.

under 400 at a place the whole shebang. you have a pm

 

[symonds86]

Re: i need some engine builder advice.

lil trick i learned, a lint free rag and some wesley tire bleach does a great job of cleaning cylinder walls after honing. gets the small filings out of the new cross hatches so the don't end up in the rings. just make sure to oil the cylinder walls after ya clean them. my engine teacher told me this when i was in college and i've done it ever since

 

[fishingman220]

Re: i need some engine builder advice.

so my buddy came today to look at the block. he said he wouldnt hone anymore, maybe alittle bit of sanding in the pits left just to get the edges off, then new rings, new rod bearing, new oil pump and slap it all back together. i need the thick intake gaskets and good quality head gaskets, any ideas on brand? and the rest that come with the kit should be fine. so some good news i guess, i am glad i didnt need to spend the money for bore and pistons. anyone else have any imput???

 

[fishingman220]

Re: i need some engine builder advice.

thanks futz i will look into those

 

[jtybt]

Re: i need some engine builder advice.

I had some casting porosity(bigger than yours) in #8 cylinder in my first 400 build. It ran fine for 5 years til I needed a little more power. Got another 400 for re-power so I sleeved that cylinder and the block sits under a bench ready for assembly if an when I need it.


...and when you get you block back from dipping, wash it with soap and water. Knock out ALL the freeze plugs(including oil galley plugs) before taking it in for dipping or dipping is a watse of time. Blow dry the engine after washing and immediately oil down the block.

 

[fishingman220]

Re: i need some engine builder advice.

i dont think i am going to dip it, do you think thats a mistake??? my guy told me to go over it with a wire wheel on a grinder and then powerwash and oil it. then put it back together and paint it.

 

[dr_bowtie]

Re: i need some engine builder advice.

if it is relatively clean you may be fine....

if there is sludge or chunks...you might opt for dipping...here is only cost 25.00 for hot tanking and cam bearings and core plugs add another 25.00 and thats for brass plugs...

on freshen up engines I dont usually tank them unless I find metal shavings...

the choice is ultimately yours...

 

[fishingman220]

Re: i need some engine builder advice.

it is preatty clean, no shavings, the paint on the outside was flakeing off, but got that off with wire wheel, i think after powerwash, it will be fine