2011 6.0L Riser and Manifold Query

Hi guys, I am new to the forum but have been using it on and off for problem solving with great results, thank you all.

I have a 2011 Crusader 6.0L in a ski boat, I am on about 650 hours now in brackish water, not heavy salt by any means. About 300 hours ago I had an overheating issue and an internal crack in one of the exhaust risers. At this time I replaced both risers with Crusader parts and gaskets and since that time the boat has been running fine. In the last 100 hours of use I noticed I was losing coolant at a steady but slow rate. I couldn't find an external leak and the performance was still 100% at all times. I did feel the exhaust smelt a bit strong. The rate of coolant loss increased recently until one morning it spat a huge amount out of the exhaust and I switched the boat off. It hasn't overheated at any time since the new risers were installed.

I figured it was a head gasket related to the previous overheat and the boat is at the shop now. The mechanic has tested the risers and again one of them has failed internally. Is this unusual? I thought the complete closed cooling system should give the exhaust components a much longer life span than 4 years and 300 hours?

My questions now are:

Could there be an underlying issue causing the repeated failure? (both risers feel the same temperature to touch)

Should I be looking at replacing the manifolds as well at this time? He says they are in reasonable shape but whilst its there I am wondering about changing it all up.

I had a look at the cooling diagram in the manual and it shows that only the tips of the risers are exposed to raw water? What is the expected lifespan on all of these components given my environment? (the boat is used regularly all year round, about 100hrs/year).

Thanks for your time

It could have been the 'new' failure was related to the original overheating issue when the first riser had it's issue....

The manifolds should last a few decades, as long as the coolant is maintained....

Your reading the coolant flow diagram is correct. The risers are service parts (need to replace) because of the exhaust gas composition, the heat flowing thru them, and the raw water.....the cast iron can only tolerate so many cycles. That service life will vary with the local environment the boat is operated in and the maintenance routine, too. around here (Chesapeake bay), the local water content varies a lot as does the maintenance - I'd say 5 years on average with decent maintenance is typical for risers though I've seen several sets go 8 years.....cheaper (thinner) versions with little maintenance are lucky to get three full seasons....so four years sounds in the ballpark....

Thanks for the quick response makomark. What you are saying fits with what I have experienced in terms of timing of the riser failure. The first one failed after about five years, at which point I replaced both, and the second went after four. I am relieved to hear that I can expect a longer life span out of the manifolds. Will get another set on order as soon as possible. I see there are a couple of other companies that make risers for that engine, am I best sticking with the Crusader OEM ones? Thanks again

Tom

to be honest, I can't tell you if the OEM parts are still made domestically....I think Barr is the only remaining domestic aftermarket source....which ever way you go, avoid the chinese parts - many reported quality issues, both here and other forums....

Last year when I was replacing what are supposed to be genuine Crusader risers and elbows, one of the risers was leaking antifreeze almost as fast as I was putting it in. The riser was leaking out one of the bolt holes. I was not very happy that it leaked but happy that the leak was on the outside and not inside. I put the old riser back on and all was well. So even new parts can leak.

Hi Ricardo

Sorry for the confusion. My setup goes manifolds straight into elbows. Its Crusader part R029016. The leak is in that elbow.

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NautiqueTom said:

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I thought the complete closed cooling system should give the exhaust components a much longer life span than 4 years and 300 hours?
Yes, typically that would be true of the manifolds.
(see below)

My questions now are:

Could there be an underlying issue causing the repeated failure? (both elbows feel the same temperature to touch)
I would have to say that the quality of the Iron Castings would correlate with a short or a long life.

Should I be looking at replacing the manifolds as well at this time?
If within the closed cooling system loop, the manifolds should be outlasting the elbows.


I had a look at the cooling diagram in the manual and it shows that only the tips of the elbows are exposed to raw water?
Yes, elbows are always Raw Water cooled and will require periodic/routine replacement.

What is the expected lifespan on all of these components given my environment? (the boat is used regularly all year round, about 100hrs/year).
Run hour time is not nearly as important as age in years is, because rust/corrosion never sleeps!

Click to expand...

Thanks for all the answers above Ricardo, I realise these are common questions that have probably been answered many times on here.

I try to flush the boat with Salt Away or Salt Off, think its a Starbrite product, how much difference do you think that makes to lifespan? Is it worth the effort?