manifolds and risers

bpmcl00 · Nov 17, 2008

Good day.

im sure this question has been asked alot but i was just wondering for my specific case

i have a 1994 mercruiser 4.3lx the boat has only been used about 50 hours last summer and sat for about 5 years prior to that. Anything before that i have no idea

What are some signs that my manifolds and risers will need to be replaced??

Also both of my manifolds were cracked at one point and had been JB welded back together.

manifolds are original and boat has only seen freshwater

Are there signs i should be looking for that they are going out ?

Thanks

Brian

Don S · Nov 17, 2008

Re: manifolds and risers

Are there signs i should be looking for that they are going out ?

Here is a HUGE sign that you need new manifolds and risers.

Also both of my manifolds were cracked at one point and had been JB welded back together.

bpmcl00 · Nov 17, 2008

Re: manifolds and risers

Don S said:
Here is a HUGE sign that you are very close to problems.

haha thanks. i talked to the guy who had the boat beofre me. he said that he didnt drain the manifolds for winter and that was how he cracked them.

besides that. what else should i be looking for as far as signs that they need to be replaced

bomar76 · Nov 17, 2008

Re: manifolds and risers

Those cracked manifolds are junk.
If they were to leak into the engine it will destroy it.
Manifolds and risers are a lot cheaper than engines.

bpmcl00 · Nov 17, 2008

Re: manifolds and risers

will i be okay just replacing the manifolds or are the risers a must too.

chiefalen · Nov 17, 2008

Re: manifolds and risers

Did you check the block to see if it was jb welded also?

Both manifold cracked?

Bet the risers need to be changed out also.

Complete osco kits on ebasic power.

Stay away from glm.

But as i have posted i would go over that block with a magnifying glass to see if it was welded also.

In the back it could crack also there are casting plugs you can't see there.

I can't believe the manifolds cracked and the block is ok.

Could be.

bpmcl00 · Nov 17, 2008

Re: manifolds and risers

Yup incredibly it was only the manifolds that cracked. the boat had only been used for about 3 of the last 8 years. 01 02 partial 03 and all of summer 08 other then that it has just sat between 04-07. also the risers and manifolds are original, and me or the owner of the last year has never had any issues with the epoxy job.

So based on all of this would new manifolds and risers be the way to go.

Or could i get away with new manifolds only.

i only paid 850 for the boat, and was just planning on just riding it out. which it has done so far.

Also fresh water use only

Don S · Nov 17, 2008

Re: manifolds and risers

I would never put old risers on new manifolds.

i only paid 850 for the boat, and was just planning on just riding it out

A FREE boat is the most expensive boat you could possibly own.

bpmcl00 · Nov 17, 2008

Re: manifolds and risers

the sad truth. so i guess ill just have to replace them.

based on the looks it seems like a pretty easy job. couple of bolts and clamps.

is this a job for a novice?

chiefalen · Nov 17, 2008

Re: manifolds and risers

When a deal is to good to be true thats the way it usually turns out.

New risers also, and you will be lucky thats all you need.

If it was so negleted how the drive oil look, and all the rubber.

How it ride, does it overheat?

When was the t-stat changed last.

Freshwater i think is what is saving you.

Me i would pull the drive also, for a look around.

Do you have a manual?

bpmcl00 · Nov 17, 2008

Re: manifolds and risers

well i took it too a mechanic beofre i bought it. he said:

transom was solid

compression was 150 for all cylinders +/- 7

Drive oil was "great" and didnt even need to be replaced

carb could use a rebuilding but would function okay without it

one stringer was Semi rotten but would hold for a couple more seasons

i told him the price and he told me if i didnt buy it he would.

He looked at the manifolds and said he had seen that happen alot and that jb weld would hold for a little while but ultimately was not a permanent fix.

other then that i have ran the boat a couple of times with no issues at all.

bpmcl00 · Nov 17, 2008

Re: manifolds and risers

bpmcl00 said:
well i took it too a mechanic beofre i bought it. he said:

transom was solid

compression was 150 for all cylinders +/- 7

Drive oil was "great" and didnt even need to be replaced

carb could use a rebuilding but would function okay without it

one stringer was Semi rotten but would hold for a couple more seasons

i told him the price and he told me if i didnt buy it he would.

He looked at the manifolds and said he had seen that happen alot and that jb weld would hold for a little while but ultimately was not a permanent fix.

other then that i have ran the boat a couple of times with no issues at all.

iv got the online manual. and have been using that studying everything and learning all i can. my next step is to change cap rotor plugs and wires.

and eventually manifolds and risers now

Chris1956 · Nov 18, 2008

Re: manifolds and risers

Change the gear oil, even if it looks good. The gearcase may be low. Grease the fittings, especially the ginball bearing (grease fitting on transom shield). Check the bellows for cracks. Change gas filter and engine oil and filter. Use straight weight (SAE-30 or SAE-40) oil or Mercruiser 25W-40 oil.

Manifolds and risers are easy to change, if the bolts are not corroded. With your freshwater useage, they should be fine. Use mercruiser gaskets (silver ones), as they are superior to aftermarket green ones. Put them on dry.

180shabah · Nov 18, 2008

Re: manifolds and risers

15 year old boat with rotten stringers and cracked manifolds for $850 - not bad if it came with a trailer.

The "chief" suggested pulling the drive - this is a must. you already know that you have rotten stringers. Your engine alignment is going to shift on the soft wood and this will destroy the coupler requiring the engine to be pulled for replacement. Also, you need to inspect/replace the gimble bearing, bellows(all 3), shift cable and the trim sender and limit switch. And, don't forget the water pump in the lower unit.

Any "new" boat will easily cost $1000 to bring it up to snuff, if you have to pay someone else to do the work figure 2-3k.

bpmcl00 · Nov 18, 2008

Re: manifolds and risers

Yes this is something i have been dreading. Pulling the drive.

is this something i can do myself. i have read alot about it. but was just wondering if it was something that i can do myself.

does this fall on the easy scale or hard scale . or in between.

i know i have you guys for help which is awesome.

sundowner205 · Nov 18, 2008

Re: manifolds and risers

Just remove the trim ram nuts, the rod that goes through from one side to the other, and the six bolts holding the drive on to the pivot housing. You may have to wiggle it to break it free.

Be sure before you reinstall it to replace the gaskets, o-rings, the impellar, & gimbal bearing.

Inspect the bellows and u-joints as well. Replace if cracked or rusted.

Finally be sure to use an alignment bar when reinstalling the outdrive. Thay can be found on ebay for $30 - 50 dollars.

180shabah · Nov 18, 2008

Re: manifolds and risers

bpmcl00 said:
Yes this is something i have been dreading. Pulling the drive....

No need for dread, pulling the drive is easy - as mentioned above just put the drive in forward gear, disconnect the trim rams, remove six nuts and pull. A gen2 alpha weighs 86lbs so you can do it yourself, but a friend is helpfull when you are ready to reinstall.

chiefalen · Nov 18, 2008

Re: manifolds and risers

Paid 300 for my boat and trailer but all i wanted was the trailer .

Paid 400 for the donor boat and trailer.

Yea get the alignment bar, i thought Dixie is using all fiberglass stringers?

Make sure it's in alignment, your gonna need that bar, and when one of your friends pull a merc ,it's free beer time for you when you bring it over.

If i were you i would call or e-mail them and see what they used in that model, year boat.

They are still in business i believe.

bpmcl00 · Nov 18, 2008

Re: manifolds and risers

yes the stringers appear to be fiberglass. but i could be mistaken. and only one is rotten towards the aft.

Also my boat was made by Dixie marine INC which is no longer manufactured.

to my knowledge dixie only makes outboard drive boats now under the name Dixie LTD

you say this job is easy so that is some relief on my part. i have been wanting to do this so i can get everything looked at, and i will be able to see any potential problems.

also the boat is due for an impeller im sure so that is something that i will be able to due while i have the whole thing off.

basically if i remove the drive and fix everything that needs to be fixed this will greatly improve the life span of my boat correct???

Thanks everyone for the much appreciated imput

Bondo · Nov 18, 2008

Re: manifolds and risers

basically if i remove the drive and fix everything that needs to be fixed this will greatly improve the life span of my boat correct???

Ayuh,....

That would be Correct......

If it Doesn't need a new set of Bellows,+ lower Shift Cable,..??....
I'd be Surprized..... Being all Original,+ all....

manifolds and risers

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