Petter Leaking Gasket Update

[Lakesailor]

You may remember I was rebuilding someone's petter AC1W after a rebore. The supplied head gasket was faulty in that the fire ring (the bit around the cylinder bore) wouldn't compress to the same thickness as the surrounding material, so the cooling water pissed out everywhere.
Anyway, a new gasket arrived from the Uxbridge Boat Centre (not the suppliers of the rogue gasket) and I fitted that. It still didn't quite compress to the same thickness as the surrounding material, but as it was on one side I smeared some Quicksilver sealing goo on that side and tightened it down to 22lbs/ft instead of 21 lbs/ft.
It started fine and ran like a bag of nails. Which means, for a Petter, that it was fine.
I nipped it down again after 15 minutes, and later that day the owner went for an hour's chugging in the rain. Ran like a dream, if dreams are noisy. He's going to nip it down again and check the tappets.
I did the bump clearance check and it was greater than 0.026" specified so we didn't need to fit the shim under the cylinder block.

Here's a little vid of the motor running. My camera records the noise as a bit harsh. When I heard it playback I was almost tempted to think the timing was a bit out, That diesel knock is frightening.
It's only just started in the vid so is still a bit cold. Why did people ever put these motors into boats?

Yes it was raining all morning through the main hatch.

 

[LittleSister]

....
It started fine and ran like a bag of nails. Which means, for a Petter, that it was fine.
... owner went for an hour's chugging in the rain. Ran like a dream, if dreams are noisy.

Most amusing!

Glad you've made progress. Impressive persistence and skill, methinks.

 

[Tranona]

Why did people ever put these motors into boats?

'cos at the time the alternatives were even "worse". Either petrol or big heavy agricultural lumps like Sabbs or early Volvos. It was the only viable small hp diesel that was light and cheap and the potential market was 25' yachts where it was better than an outboard. Only lasted a few years as boat size moved up and the Yanmar 1GM came in to take the low hp end.

 

[Lakesailor]

I used to have the twin cylinder air-cooled one on some water jetting-pumps. They were noisy beasts. Very reliable though.

 

[rotrax]

At first I thought it was one of Sam Springer's Narrowboats fitted with the air cooled Ducati diesel-equally noisy!

Glad you resolved the problem-might help someone else in the same situation.

 

[doug748]

I loved my twin, and the row.

It was a very reliable old chum, I found the rattle oddly reassuring.

 

[mtb]

sounds like diesel knock to me if it's not air in the system it may be an iffy injector or timing to advanced

cheers
mick

 

[rob2]

Obviously a youngster - or never driven an old dumper truck around a building site. That's exactly what it's supposed to sound like.

For all those who think things have improved greatly, it's always at some expense. Engines have to be heavier built than the Petter, just to incorporate enough material which can be shaped to absorb the sound rather than resonate. Anyone who tells you that a BMW car is quiet has never sat in front of one doing 50mph in a wind tunnel - sounds like a tractor without all that sound insulation that protects the cabin!

True, there is something very reassuring about an engine making the right sound for its type, no matter how loud. I could sleep in the quarter berth with the engine going full chat, but if it hiccupped, I'm awake immediately.

Rob.

 

[rotrax]

Obviously a youngster - or never driven an old dumper truck around a building site. That's exactly what it's supposed to sound like.

For all those who think things have improved greatly, it's always at some expense. Engines have to be heavier built than the Petter, just to incorporate enough material which can be shaped to absorb the sound rather than resonate. Anyone who tells you that a BMW car is quiet has never sat in front of one doing 50mph in a wind tunnel - sounds like a tractor without all that sound insulation that protects the cabin!

True, there is something very reassuring about an engine making the right sound for its type, no matter how loud. I could sleep in the quarter berth with the engine going full chat, but if it hiccupped, I'm awake immediately.

Rob.

If you listen to a diesel injector pump on a test/calibration rig, they often sound just like an engine.

Two identical Citroen diesel cars sounded totally different depending on which injector pump was fitted-Rotodiesel was quiet, Bosch was much noisier.

I went into the Dynomometer room when one of my race engines was producing full power at high RPM once to make a tiny adjustment.

I feared for my life. The noise and air vibration was appalling.

When I told the tuner, the late Leon Moss, he replied that that is why he sent me in to do it...................................

 

[NickRobinson]

Call that a tad noisy?

Try six hours of one of these Yanmar YSM 8/12/hp ( and no, the one in the video isn't sick...)

http://www.youtube.com/watch?v=1inLxeYnnK8

 

[rotrax]

Call that a tad noisy?

Try six hours of one of these Yanmar YSM 8/12/hp ( and no, the one in the video isn't sick...)

http://www.youtube.com/watch?v=1inLxeYnnK8

WOW-not anything like the one First mate and I had in a 40 foot Narrowboat.

We would sometimes do 10 or 11 hour days in midsummer-engine never stopped all day.

We certainly would not have if ours had been like that one!

 

[NickRobinson]

Speak up, I can't hear you! ......

 

[Lakesailor]

sounds like diesel knock to me if it's not air in the system it may be an iffy injector or timing to advanced

cheers
mick

He had the injector serviced and I bled the fuel line without any hitch. I wondered about timing, but on balance it is just a noisy engine in an enclosed and hard-surfaced space. Lovely and quiet on the over-run

 

[mtb]

Obviously a youngster - or never driven an old dumper truck around a building site. That's exactly what it's supposed to sound like.

For all those who think things have improved greatly, it's always at some expense. Engines have to be heavier built than the Petter, just to incorporate enough material which can be shaped to absorb the sound rather than resonate. Anyone who tells you that a BMW car is quiet has never sat in front of one doing 50mph in a wind tunnel - sounds like a tractor without all that sound insulation that protects the cabin!

True, there is something very reassuring about an engine making the right sound for its type, no matter how loud. I could sleep in the quarter berth with the engine going full chat, but if it hiccupped, I'm awake immediately.

Rob.

core blimey cheers nice to be called young ;-)
30 odd years in marine building/plant mechanical engineering doesn't count then
I have three ac2 engines sat here at the mo rebuilt one or fifty in my time, but of course at my age ;-) what do I know

 

[Lakesailor]

The gasket from Uxbridge worked. Thanks for that. I only used goo on the side with the proud fire ring. Seemed to work OK. I didn't check the timing. It's the same as it was before we touched the engine. He only uses it to leave and return to a swinging mooring on Windermere, so the motor is not critical. I did suggest sticking an outboard on the stern instead.