Exhaust risers do it yourself??

7B Complete V-6 Exhaust kit (4" Elbow)

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Fits mercruiser V-6 models Inc gasketsCast iorn ConstructionREF # 58222

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[SIZE=+1](800) 349-2628 ... (504) 888-2798 ... Fax (504) 888-2881[/SIZE] Here are some aftermarket parts, I believe they are GLM or osco. I put them on my new engines 4 years ago with no issues. I can't see Merc parts being that much more? Do I have the correct parts listed for your engine? If you are changing them every 3 years I would not hesitate to use them. Merc gaskets are a good idea. They make a 3 and 4". Any comments? I use these guys all the time for most parts and have never had a problem. But then again I don't take my car to the dealer for the expensive parts either. :huh:

That's more in line with what I figured they should cost, maybe $500 or $600 per engine...
 
That Photo was taken at a beach in Bimini Bahamas.

We were on a MarineMax getaway, my boat has the tan top.
 
Do the Aftermarket parts have ceramic coating?
 
Uh no. I was quoted $2100 for a set of manifolds and risers, gasket kits etc, for my 5.7L. This was for the newer style dry fit ones.

If you find 2 new engines for <$5k buy them.

I agree, when I bought my boat, the owner had bar's on and part of the deal was to go back to OEM parts, this included new bolts, clamps etc. plus in my case elbows. The total for parts alone FOR ONE engine, NO LABOR included, (Priced at three different locations was right at $2,950.00 per engine). so if you can do the comment below I would say go for it:thumbsup:

...If you find 2 new engines for <$5k buy them.
 
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I did that job myselt. Not bad at all. The old cast iron ones were very heavey. I put on GLM aluminum powder coated ones and so far so good. Use new bolts when replacing I think most of the parts came in the kit. $695.00 per side

Rick
 
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I just did both engines in mine a few months ago. It's not a difficult job but is time consuming and your back will be sore afterwards. Couple of recommendations - have some towels in place so you can place new and old components on the deck without marks and make sure you have a good torque wrench handy - it is easy to over torque these bolts. On the 4.3 - the bolts should be torqued in 2 steps - one to about 10-15ft/lbs and then the final setting going from the center to the outsides. The final torque setting on mine was 22ft/lbs. I used anti-seize on the bolts to make it easier to do future inspections - it can get a little messy so another reason for towels! Depending on the condition of your bolts it may make sense to replace them - the Mercruiser bolts are expensive but I felt good about going with all OEM including gaskets. Make sure the riser gaskets you get match up - the first set which came in for me did not have all of the cooling passages cut out.

BTW - I was advised to not get ceramic coated manifolds or risers. The reason is the iron and the ceramic coating expand/contract to heat at different rates. This can cause the coating to crack, salt water to get in and then stay in even if the engine is flushed. Apparently the cracks will open up when running hard and they are extremely hot and normal flushing at the end of a trip wont flush it all out. Not sure - I wasn't really in the market anyway but wanted to pass it along. Any thoughts on this?
 
Love it or leave it, here's Mercruiser pricing:

The mani's are $374.17 each.
The risers are $307.75 each.
Elbow gaskets are $40.50 each.
Mani gaskets are $8.30 each.
 
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I couldn't find a 2003 v6 engine exploded parts diagram but these numbers are from a 1997 - not sure if there's a difference btwn a 1997 and a 2003 4.3L Merc. Prices are from B0ATFlX.com. These are not ceramic coated products. If you're changing them ever 4-5 years, I don't see the sense in ceramic...

Manifolds: 192.38 x 4
Riser Kit: 3" 239.71; 6" 377.21 (I don't know which height you need but all gaskets, nuts and bolts come with the kit) x 4
Elbows 174.55 x 4
manifold to riser

Looks like about $2500 in parts for the 3", an additional $420 if you need the 6" riser kit.

I ordered 260lbs of cast iron from these guys 2 weeks ago - the UPS was $21 and it came in 2 business days ( I think they shipped from NH). That is not a type-o. Something that surprised me was that the manifolds came with a gasket in the box. Not realizing this I had ordered 4 gaskets a'la' carte which added about $40 to my total. Not sure if your manifolds will come with a gasket. BTW, these are genuine Mercruiser parts. I'd avoid the aftermarket stuff.

Are you certain you need manifolds after three seasons? I can see elbows/risers, but that service interval for manifolds seems excessive.
 
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It doesn't hurt to have the additional gaskets - minimizes the downtime when you go and do an inspection down the road. Now you just need to keep track of them!

I looked at the Osco and Barr products when I was in the market - I ended up getting a really good deal on Mercruiser so stayed with what had lasted approx 5 years. I'm a little surprised you need new ones every 2-3 years - that's an expensive thing to replace if you don't necessarily need them. If you have needed them that often in the past you may want to do good fresh water flushes after each use to prolong the lifespan.
 
What beach in Bimini?

I just did 4 elbows on my boat. Cost was $175 each for Merc parts. While I like Merc exhaust parts, I've had bad luck with the Merc gaskets. I've been using Sierra's and some red RTV. Seal better and are easier to remove the next time
 
Just my $.25 but, if you are changing out Merc manifolds every 3 years, why not just renew the gaskets instead? In almost all cases, the failures are from the gasket interface NOT the cast iron.
If you are going to continue to change out the manifolds, go with Barr or osco.... way cheaper and will last 5 years just fine.
ps: the one manifold I would not use is aluminum.... they do not belong on a boat imho...
 
okay,, good input ,,

Marine max recommends replacement every three years, I run in salt Water and I do flush out.

The look brand new on the outside, no corrosion so I could take the risers off , to inspect ,,, can you determine if they are in need of replacement at that point?
 
Panchita, on your hot water heater, is it on your port side behind the batteries? If its there I have replaced them. what a Pain in the a%#*. You have to remove all of the batteries that are in front and the board that is mounted ontop of the heater that probably has the fresh water pump on it. Then disconnect all hoses and wiring. The hard part is getting to the back screws that you cant see behind the heater. What happen to your heater? Did it rott out from salt water? thats what usually happens to the heaters. If it has, When you put the new one in don't hook up the salt water lines. These lines heat the water in the heater by the port engine running. But actually if they were hooked up they clogged in about a year anyways. Take the hoses off the motor and get 2 plugs and plug the holes they came from. the size of the plug is the same size as your drain plug. Or an easier way is remove one of the hoses from the motor and use the other hose thats still on the motor and plug it in to the spot where the hose was that you removed.

Also on exhaust, Like leafy isle said don't use the aluminum exhaust manifolds. They will rott out down there, and don't use aftermarket, I see so many problems with aftermarket exhaust leaking water back into the engines. I think your motor has the newer dry joint exhaust, If it does I don't think theres companies making that in aftermarket but I would stay away.
 
yes,,it is on the port side, the heater leaks , and it looks to be a pain,, .

I am going to order all original parts, yes it is the dry Joint system,,, I have my mechanic in the boat yard will do the labor for $275 per side if I decide not to do it.

Is there a way to accurately and confidently inspect the system without taking the manifolds off but rather just the elbows?

is the recommended 3 year change out interval accurate?
 
On the newer style exhaust theres not much to see when you pull it apart. the only thing you can check is by pulling the elbow off and looking at the snout and seeing how corrodded it is. All the ones newer style exhaust that were going bad looked new on the outside but had a crack inside where you couldn't see. Again on the new style exhaust you don't have to worry about the riser gaskets leaking, because its almost impossible for it to leak from the water side and back into the exhaust side. different set up from the older exhaust
 
My mechanic ( Mercruiser certified ) had me change my manifolds and risers every five years on my 260. It was salt water cooled and never had any problems...:wow:
 
I have a guy name is Todd that could set you up with a mechanic to do all of the work you need. If interested his number is 754-581-2812. With the heater if your replacing it you can probably find it on ebay allot cheaper.

I think your exhaust should last longer if you are really flushing them out all of the time. Most people say they do but aren't.
 

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