My yanmar diesel (27 hp, 3 cyl) for my hunter 36 has had two incidents 4 years apart where the seawater exhaust from the engine cooler Gary’s blocked at the nipple on the outlet leading to the exhaust gooseneck. These are carbon steel and i get they rust. Anyone have a more permanent solution they have done instead of keep replacing the steet nipples every few years?
Yanmar Diesel cooling blockage at street nipple to exhaust
- Thread starter bris59
- Start date
I take it when you say "street nipple" you are referring to a "close nipple" ?
A street fitting has a male thread (MPT) on one end and a female thread (FPT) on the other end.
Still close enough for our needs. Your carbon steel nipple can be replaced with a hex bronze or SS nipple from Groco or other marine supply store at a small fraction the price of the specified engine part price.
If I'm on the wrong track here, please post a picture of the offending nipple where it attaches to the mixing elbow and we'll ses what's available.
A street fitting has a male thread (MPT) on one end and a female thread (FPT) on the other end.
Still close enough for our needs. Your carbon steel nipple can be replaced with a hex bronze or SS nipple from Groco or other marine supply store at a small fraction the price of the specified engine part price.
If I'm on the wrong track here, please post a picture of the offending nipple where it attaches to the mixing elbow and we'll ses what's available.
Had the same problem with my volvo penta. Found these folks on the internet. stainless wont fill up your nipple with scale.
hdimarine.net
not advertising just a happy customer
GM Stainless Steel Mixing Elbow - HDI Marine
Replaces Yanmar PN: 128370-13600 / 128270-13600 / 124070-13520 / 128370-13610 / 104214-13531 /128990-13520
hdimarine.net
not advertising just a happy customer
the engine cooler Gary’s blocked
No, Gary hasn't blocked anything. I promise!!!
As mentioned, in order of preference, Bronze, Stainless, Brass.
You are looking for a Barbed nipple. Either straight or as an elbow.The barb accepts the hose and the screw end screws into the exhaust.
Bronze straight
Bronze elbow.
Stainless straight.
Stainless elbow.
Brass straight
Brass elbow
No, Gary hasn't blocked anything. I promise!!!
As mentioned, in order of preference, Bronze, Stainless, Brass.
You are looking for a Barbed nipple. Either straight or as an elbow.The barb accepts the hose and the screw end screws into the exhaust.
Bronze straight
Groco Bronze Pipe-to-Hose Adapter - 1/2'' Pipe 1/2'' Or 5/8'' Hose | eBay
Groco 1-1/2" 90 Degree Hose Thru-Hull Fitting [HTHC-1500-S]. Perko 2" Pipe to Hose Adapter 90 Degree Bronze Made in The USA (39143). Tailpipe Hose Adapters Tail Piece 1" Mpt > 1" Hose. Moeller Brass Fuel Line Hose Barb (Female 1/4" NPT x 3/8").
www.ebay.com
Bronze elbow.
Stainless straight.
Amazon.com
www.amazon.com
Stainless elbow.
Amazon.com
www.amazon.com
Brass straight
Brass elbow
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A little more information would be helpful, what model number Yanmar there are several 3 cylinder Yanmars? Can you post a photo of the part that is blocked?
?All - thanks for the replies! I did a methodical step by step replacing the impellor on my 3GM30F and checked cooler flow. I checked the backflow preventor and found flow 1/5 what it should have but as with many others, the problem was with the cast iron goodeneck and fitting for the seawater discharge. I replaced with a stainless steel with a bronze fitting for the seawater discharge. Flow is much much better than I have had since buying the boat 5 years ago. I purchased the new exhaust gooseneck and fitting from HDI Marine for $350 and did the work myself. Great company and they were very helpful answering all my questions.