Has anyone had engine issues caused by the Tiara exhaust systems of a mid 1994 era boat. I ask this question because I have a 1994 4000 express and am working through some performance issues. Over on the boat diesel forum, people are saying my factory exhaust system is a recipe for disaster and will destroy my turbo's. I don't see the problem in the system. Rather than get into a lengthy debate over there, I thought I'd ask Tiara owners if any of you have had problems.
I don't think I would come to that conclusion. I have read your post on boatdiesel as I have been a member there for years. The only sure way to determine if your stock Cummins exhaust 'riser' (not really risers since they point down) have been compromised to is to remove and inspect. Stock Cummins risers need to be inspected and replaced as they are steel and will rust internally allowing salt water to flow into the turbo. From some of the photos posted, it does look like the water line is close to the exhaust turbo outlet that it may allow splash back of salt water at times, not all the time but I can see where there could be an issue. My exhaust, 6bta 370hp 3500 Open, is not stock Cummins but made my Marine Exhaust in FL. It has a high riser and the raw water is on the downside approx. 20" away from the turbo exhaust outlet. If I was you, I would remove the turbo exhaust coupling and have a look, won't take that long and will tell you loads of information.
Thanks for the update, next time I'm there, I will pull the riser and see if it is telling me anything. I'm also adding fresh water flushing to the engines, planning on giving each engine a full 10 minute flush after use. This should increase the lifespan of components and reduce risk of salt mist damaging turbo's.
Would you mind sharing how much your custom risers cost? Thanks
My technician replaced both risers from Marine Exhaust Systems, this past weekend, on my '01 35'Open (Cummins 370's). $2,125.00 + tax ea. Labor was about 3 hours.
The risers are made by Marine Exhaust Systems, as Mikes above, but they were/are original equipment from Tiara. So, I haven't had to replace them as of yet but $2125, IMO, is a good price.
Mike, why were your replaced? Did they break?Leak?
I agree that is a very good price, my mechanic told me that the stock cummins replacements would run 1,200 per side plus his time to install. If and when I do a replacement, I'll modify the system with drystack rise, then water spray on the downslope. Hoping to retain as much of the existing exhaust system as possible.
(11-23-2015, 09:03 AM)trit21 Wrote: The risers are made by Marine Exhaust Systems, as Mikes above, but they were/are original equipment from Tiara. So, I haven't had to replace them as of yet but $2125, IMO, is a good price.
Mike, why were your replaced? Did they break?Leak?
As the original owner, I was notified by Tiara that the OEM risers needed to be replaced (a field service campaign), and was handled by my dealer, Allied Marine. This was back in '02 or '03. Tiara paid for it (a good thing!).
Recently, we started to smell diesel exhaust in the cabin while underway. Investigating, our technician found a crack on the port engine riser and some small leaks on both sides, and recommended replacing.
I think 12 to 13 years is a great service life, as my engines have over 2900 hours on them.
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