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  Topic Review (Newest First)
12-25-2006 01:17 PM
Giulietta Mine is a 3 cylinder normally aspirated and it is not the one on your picture.

Mine is a Saildrive model and the air filter is separated from the rest. Kimb could be right I did not look inside, but I believe it's a chcane type.

As soon as possible I get some photos and will come back here again.
12-24-2006 07:52 PM
k1vsk Kimberlite
I originally asked this question because someone on another board described some serious engine problems as a result of sucking in the remnants of a shreaded belt.
My intent wasn't to debate the need for a filter. I was asking more to find out what, if any effect the filter could have on engine performance as there isn't any design spec from whcih I can homebrew my own flter to go in the silencer.
It makes sense dust sized particles would not cause any catastrophic damage, certainly in the short-term, but this guy had some belt fragments do a job on a couple of valve seats and springs requiring some head rework. I guess it could have been worse...

Any yes, I have talked to Yanmar folks - two tech types at different time and guess what? Got conflicting answers...
12-24-2006 06:00 PM

The grey plastic thing on the alternator and raw water pump side of the engine is a water lift muffler--probably made by vetus.
this is just a silencer for the exhaust and prevents a water siphon.
on the side of the engine with the oil filter is a can shaped device with a screen and a couple of latches on it. this is the "air cleaner" and has no filter inside and keeps big things from getting into your engine intake. i have used my 100hp turbo in africa and have had the red dust from the sahara all over the boat without any engine problems. the engine is a 2002 model and has 1800 hours on it.
fair winds,
12-24-2006 05:53 PM

i have the 4jhshte 100+ hp turbo intercooled engine on kimberlite.
thete is just a metal screen on the silencer to keep out big particles.
there is no filter on this engine.
fair winds,
12-24-2006 12:54 PM
camaraderie Loooks like at least some of the new 4JH's have some sort of filter on them.
Maybe it is for the turbo models as I understand the turbo mechanisms are sensitive to dirt??? you have a turbo or natural air model?
12-24-2006 12:51 PM
billangiep Giulietta,
Could the tube comming out of the heat exchanger going to the seperate silencer be a water lift muffler?
12-24-2006 12:39 PM
RichH You sure do get dust from North Africa. Ever wonder why the snow in the Alps is sometimes .... sooooooo yellow? or the Italian sky is soooooo blue?
12-24-2006 08:06 AM
Giulietta Now I am getting confused. My engine has a silencer and it is separated from the air filter.

If only I could post the photo. I have a grey plastic air filter, on one side of the engine, in its rear, and on the other side the exhaust tube comes out of the cooling water heat exchanger, into a separate silencer that also prevents sea water from returning to the engine (syphon??).

My engine was made in 2006, could it be that they modified it??

However the Yanmar guy told me the air filter is needed. Maybe we get too much dust from North Africa!!

Apparentely over there you only get COLD AIR from Canada!!
12-23-2006 11:38 PM
4jh air filter

I have had a 4jh engine on two boats.
15,000 miles on one and 21,000 miles on the other all without a filter. my curent engine has a turbo also without a filter element.
it is not necessary according to Mack Boring, the east coast yanmar distributor.
faie winds,
12-23-2006 06:57 PM
camaraderie I had a 4JH...there is no air filter and none is necessary. Their is a piece of what I would call "gauze" on the inner side orf the air intake which may need cleaning now and then from any oil "blow back" to preserve air flow.
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