Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 11-11-2015, 00:25   #31
Registered User

Join Date: Aug 2012
Posts: 811
Re: broken rocker arm shaft mounts

Quote:
Originally Posted by Celestialsailor View Post
A little contradiction there.
Ya... he was delivering but did you check the water and thermostat after the engine work was done. From what i read, you were the last guy to touch it.


Good point and also piston clearance. On my Westerbeke W46 there was .010" (Ten thousands of an inch) from the top of the piston to the bottom of the head. Any resurfacing of the head is going to change the dynamics of the function of the engine. This is why it pays to read the specs from the engine manual as to what can be machined safely.
Diesel engines with their high compression ratios around 22:1 have much smaller combustion chambers than petrol / gasoline engines in cars which are now around 9.5:1. This means that clearance between the valve head and the piston crown is much smaller in diesel engines. Anything planed off the cylinder head will reduce this clearance further bringing the overhead valves closer to the piston by the amount removed.

It's possible that a workshop used to machining car cylinder heads might have taken too much off. It's also possible that this may have been the second time it was planed.

My suggestion of the wrong valve clearance was an objective / constructive observation not a personal criticism. It is certainly one of the possibilities.

Obviously something was wrong.
__________________

__________________
GrahamHO is offline   Reply With Quote
Old 11-11-2015, 07:41   #32
Senior Cruiser
 
skipmac's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: 29 49.16 N 82 25.82 W
Boat: Pearson 422
Posts: 12,388
Re: broken rocker arm shaft mounts

Quote:
Originally Posted by jonahmcg View Post
hey guys, i did adjust the tappets of course. but thanks for the insults. i didn't check the cooling because i wasn't on the boat. he was delivering it. so sort of hard to get into the engine and check things out. ya know.
Hey Jonah,

Just ignore the insults. Always find a couple like that almost anywhere you go, even Cruisersforum.

Do keep us posted on what you find. I'm very interested to learn the answer to this little puzzle.
__________________

__________________
The water is always bluer on the other side of the ocean.
skipmac is offline   Reply With Quote
Old 11-11-2015, 11:06   #33
Registered User

Join Date: Aug 2012
Posts: 811
Re: broken rocker arm shaft mounts

Quote:
Originally Posted by skipmac View Post
Hey Jonah,

Just ignore the insults. Always find a couple like that almost anywhere you go, even Cruisersforum.

Do keep us posted on what you find. I'm very interested to learn the answer to this little puzzle.
Hey Jonah,
These are not personal insults! People are trying to help you. Someone, somewhere has done something wrong. These things don't happen by themselves.
Here is another possible scenario. There should be an oil line taking the engine oil from the engine block to the cylinder head and into the rocker shaft. On disassembly and head removal this oil line has to be removed. It has short hollow banjo bolts at each end. If those bolts had been screwed back into their respective holes for safe keeping, and if the oil line had been omitted on reassembly the valve gear would seize up after say 15 minutes ( as it apparently has). There would be no oil leak as the banjo bolts were put back into their holes for safe keeping.
On my Yanmar, that oil line runs from near the air intake but on the block; then around behind the engine and up into the back of the cylinder head.
Likewise on your engine there may be another way to transfer the oil to the head? It could be an oil way in the block matching an oil way in the head; perhaps. This would necessarily be through a hole in the head gasket. If that were blocked with gasket goo for example the valve gear would seize. I doubt that it is possible to replace the head gasket the wrong way up but it may be possible and that may obstruct the oil way.
__________________
GrahamHO is offline   Reply With Quote
Old 11-11-2015, 11:30   #34
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 19,371
Re: broken rocker arm shaft mounts

Quote:
Originally Posted by a64pilot View Post
In any event I'd pull the head, just because I strongly suspect bent valves and I would have to rule that out.
Of course an easy way to check for a bent valve is once the head is off, lay it on it's side and fill the intake or exhaust ports with alcohol, a bent valve will leak badly.
Look for shiny spots on the pistons, usually looks like little crescent moons.

I've seen a few hydro locked motors, but never seen the valve train damaged by a hydro lock, not bent pushrods etc.
I had it happen on my Perkins 4-236. Motor had less than 500 hours on it. The exhaust was large (3") and the muffler small. The Exhaust outlet was half submerged at the water line. Evidently when I parked it for the night at a marina, the wind chop direction was putting just a bit of water in the exhaust with each lapping wave. When we started it up in the am it cranked very hard, started and then had a problem.
After a lot of screwing around we removed the rocker cover and found one pushrod off the rocker on the aft/lowest cylinder. Not sure how that happened but it seemed to be from some water in the cylinder. Maybe when it fired off with some water in there (non compressible) as opposed to all gas it forced the valve up and bent the pushrod off the rocker. Go figure. I had a custom exhaust loop made after that.
__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is offline   Reply With Quote
Old 11-11-2015, 12:08   #35
Registered User

Join Date: Aug 2012
Posts: 811
Re: broken rocker arm shaft mounts

Quote:
Originally Posted by Cheechako View Post
I had it happen on my Perkins 4-236. Motor had less than 500 hours on it. The exhaust was large (3") and the muffler small. The Exhaust outlet was half submerged at the water line. Evidently when I parked it for the night at a marina, the wind chop direction was putting just a bit of water in the exhaust with each lapping wave. When we started it up in the am it cranked very hard, started and then had a problem.
After a lot of screwing around we removed the rocker cover and found one pushrod off the rocker on the aft/lowest cylinder. Not sure how that happened but it seemed to be from some water in the cylinder. Maybe when it fired off with some water in there (non compressible) as opposed to all gas it forced the valve up and bent the pushrod off the rocker. Go figure. I had a custom exhaust loop made after that.
I'm sure you have corrected the muffler / water lock size by now. Also you need a high loop in the exhaust pipe before the exit.
I made a little flapper valve out of a small sheet of copper on a plastic hinge for the end of my pipe outside the transom. It's cut on a 45* angle so it closes, like you see on truck exhausts. It's mainly to stop the salty air blowing through the pipe into the engine. The water lock should prevent that but it's an extra precaution for if the boat is sitting unused for a while.
__________________
GrahamHO is offline   Reply With Quote
Old 11-11-2015, 12:12   #36
Registered User
 
Terra Nova's Avatar

Join Date: Apr 2007
Location: Marina del Rey, California
Boat: Freya 39 cutter- Terra Nova
Posts: 3,652
Re: broken rocker arm shaft mounts

Quote:
Originally Posted by GrahamHO View Post
...you need a high loop in the exhaust pipe before the exit...
From the water lift muffler the exhaust should rise as directly as possible to the high loop, and then continually downward to the outlet.
__________________
1st rule of yachting: When a collision is unavoidable, aim for something cheap.
"whatever spare parts you bring, you'll never need"--goboatingnow
"Id rather drown than have computers take over my life."--d design
Terra Nova is offline   Reply With Quote
Old 11-11-2015, 19:27   #37
Registered User
 
Celestialsailor's Avatar

Join Date: Nov 2006
Location: In Mexico, working on the boat
Boat: Hallberg Rassy 35. and 14ft.Whitehall pulling skiff.
Posts: 8,013
Images: 5
Re: Broken Rocker Arm Shaft Mounts

I feel I need to address the hurt feelings and insult issue. Ultimately we are responsible for our choice in life and with our property. Personally, I run into it all the time. Examples are:1) Having a friend move my boat from the slip to the marina hoist, while I'm at work. The starter stuck that I had problems with it prior. I forgot to tell my friend this information. I assumed if it stuck they could discern the sound of a stuck starter from that of the diesel engine. They couldn't or didn't. Price: New starter. I blamed them in my mind for about 10 minutes until I realized it was me that set that scenario up. So I was wrong, not them.
2) I had head work done on the head of a diesel. Got it back without the valve stem caps. I swore it was their fault (again in my mind) until I looked in every box in my shop and found them under a flap of a box. This, when the guy doing the valves distinctly told me not to disassemble the head myself. But I did, thinking I could save a few bucks.
One thing I know...if I touch it, I have a possible part in it's demise. I've learned not to go on the Internet with my blame thrower pointing fingers. If I was having someone delivering a boat for me, I would do what I could to minimize problems. It's not the delivery persons responsibility to make sure the engine installer properly tested the engine for any water locks, thermostat or any related malady that could occur. Sure, it would be nice if the person could keep and eye on things but he is part of the human condition and with that we get what we get.
One thing not mentioned...that is...almost every engine panel I know has a high temp alarm. That was never mentioned going off. Why is that? Maybe the installer (new owner) neglected to hook it up. Maybe it was faulty and untested. Again, the responsibility of the owner. If I'm being labeled here as "having a bad day"...forget it. I'm not. Over time and being self sufficient, I tire of people blaming and then asking for help. That's a victims role not a self sufficient sailor. Sorry for the rant. Just wanted to clear the air on this one.
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: Wow - what a ride!"

http://wwwjolielle.blogspot.com/
Celestialsailor is offline   Reply With Quote
Old 11-11-2015, 19:31   #38
Registered User
 
Terra Nova's Avatar

Join Date: Apr 2007
Location: Marina del Rey, California
Boat: Freya 39 cutter- Terra Nova
Posts: 3,652
Re: Broken Rocker Arm Shaft Mounts

Cs--good post.
__________________
1st rule of yachting: When a collision is unavoidable, aim for something cheap.
"whatever spare parts you bring, you'll never need"--goboatingnow
"Id rather drown than have computers take over my life."--d design
Terra Nova is offline   Reply With Quote
Old 11-11-2015, 19:59   #39
Guy
Registered User

Join Date: Feb 2013
Location: So. Oregon, USA
Boat: Seafarer36c
Posts: 4,308
Re: Broken Rocker Arm Shaft Mounts

Yes and it relates to always blaming the mechanic right away, too.
__________________
Guy is offline   Reply With Quote
Old 11-11-2015, 21:02   #40
Registered User

Join Date: Aug 2012
Posts: 811
Re: broken rocker arm shaft mounts

Quote:
Originally Posted by Terra Nova View Post
From the water lift muffler the exhaust should rise as directly as possible to the high loop, and then continually downward to the outlet.
Exactly, and the loop should be in line with the boat and not off to one side assuming a transom exit. If it loops to one side and you are motor-sailing, water can collect in the loop if you are heeled that way. Then you shut down the motor and tack, and the water in the loop is now on the high side and can cascade back into the engine.
You need to work out all the possibilities for your own boat. A side exit is different again.
__________________
GrahamHO is offline   Reply With Quote
Old 11-11-2015, 21:28   #41
Registered User

Join Date: Aug 2012
Posts: 811
Re: Broken Rocker Arm Shaft Mounts

Celestialsailor we all learn by mistakes and we have all made them.
It can be a good 💡 idea if you are going to disassemble anything new, to take some cellphone photos of the different stages to refer to on reassembly.

It's not a bad principle to do things yourself and get a specialist to do what you can't. I do that all the time and save lots of money.
Right now I'm finishing making a short prod for an asymmetric gennaker.
I cut all the SS components and took them to a welder to weld. He knows I wont blame him if I get it wrong.
__________________
GrahamHO is offline   Reply With Quote
Old 12-11-2015, 01:10   #42
Registered User

Join Date: Nov 2013
Location: Slidell, La.
Boat: Morgan Classic 33
Posts: 1,105
Re: Broken Rocker Arm Shaft Mounts

Quote:
Originally Posted by jonahmcg View Post
So here's the story, Bought a sailboat this summer, guy delivering it didn't check the cooling water, blew a head gasket on the way up. Got the head skimmer, put a new gasket in, reconnecting everything. Ran it for fifteen minutes, changed the oil. Seemed to run fine, Tried to start it again, a loud banging was happened every two or three seconds. Took the rocker cover off and found 2 bend pushrods and two of the mounts for the rocker arm shaft have split in two.

any ideas on why/how this would happened.
Sounds to me like a basic synopsis, no blame inferred. When I get on a boat I'm unfamiliar with, I don't leave until I'm confident in its' ability. The captain is responsible for the boat, the owner is responsible for the bills for running the boat.

Quote:
Originally Posted by jonahmcg View Post
i didn't do any valve adjustment.

Im at the point in the process now where i've ordered new parts and am going to take the head back off, check the piston clearances, and put it back together. still havent diagnosed why it happened though so a little worried i might just happen all over again.
Quote:
Originally Posted by jonahmcg View Post
is this something that could have happened if someone tried to start the motor too long with the seacock open, and the water from the exhaust backed into the engine?
Quote:
Originally Posted by Celestialsailor View Post
That's exactly what happened. You didn't adjust to make up the difference the head lost. BTW nice job blaming the chap that didn't check the cooling system...you didn't? Why not?
Celestial Sailor, Good job, god. Wish I had your all-knowing prescience.

Quote:
Originally Posted by jonahmcg View Post
hey guys, i did adjust the tappets of course. but thanks for the insults. i didn't check the cooling because i wasn't on the boat. he was delivering it. so sort of hard to get into the engine and check things out. ya know.
Quote:
Originally Posted by Celestialsailor View Post
I feel I need to address the hurt feelings and insult issue. Ultimately we are responsible for our choice in life and with our property. Personally, I run into it all the time. Examples are:1) Having a friend move my boat from the slip to the marina hoist, while I'm at work. The starter stuck that I had problems with it prior. I forgot to tell my friend this information. I assumed if it stuck they could discern the sound of a stuck starter from that of the diesel engine. They couldn't or didn't. Price: New starter. I blamed them in my mind for about 10 minutes until I realized it was me that set that scenario up. So I was wrong, not them.
2) I had head work done on the head of a diesel. Got it back without the valve stem caps. I swore it was their fault (again in my mind) until I looked in every box in my shop and found them under a flap of a box. This, when the guy doing the valves distinctly told me not to disassemble the head myself. But I did, thinking I could save a few bucks.
One thing I know...if I touch it, I have a possible part in it's demise. I've learned not to go on the Internet with my blame thrower pointing fingers.(then why are you doing it?) If I was having someone delivering a boat for me, I would do what I could to minimize problems. It's not the delivery persons responsibility to make sure the engine installer properly tested the engine for any water locks, thermostat or any related malady that could occur. Sure, it would be nice if the person could keep and eye on things but he is part of the human condition and with that we get what we get.
One thing not mentioned...that is...almost every engine panel I know has a high temp alarm. That was never mentioned going off. Why is that? Maybe the installer (new owner) neglected to hook it up. Maybe it was faulty and untested. Again, the responsibility of the owner. If I'm being labeled here as "having a bad day"...forget it. I'm not. Over time and being self sufficient, I tire of people blaming and then asking for help. That's a victims role not a self sufficient sailor. Sorry for the rant. Just wanted to clear the air on this one.
Feeling a little guilty? Good. Rant all you want. The introductory post states very clearly that the OP bought a boat and arranged for someone to deliver it to him. Since we can't know if the owner told the captain that the boat was competent to make the trip, the worst case is to assume that he didn't. If that is so (and actually, even if he did say it was competent), the responsibility is on the skipper to make sure that the boat could survive the trip, if only in the interest of self-preservation. If he didn't, and the worst thing that happened is he burned up the engine, he should consider himself lucky, and, as appears to be the case, hope that the owner doesn't hold him responsible in some way. (Assume I'll get some flack on that one though...)

Of course, it seems a moot point, since it doesn't appear he's coming back. Again, good job, experts.


Quote:
Originally Posted by GrahamHO View Post
Celestialsailor we all learn by mistakes and we have all made them.
It can be a good �� idea if you are going to disassemble anything new, to take some cellphone photos of the different stages to refer to on reassembly.

It's not a bad principle to do things yourself and get a specialist to do what you can't. I do that all the time and save lots of money.
Right now I'm finishing making a short prod for an asymmetric gennaker.
I cut all the SS components and took them to a welder to weld. He knows I wont blame him if I get it wrong.
Always nice to hear some calm good sense.
__________________
jimbunyard is online now   Reply With Quote
Old 12-11-2015, 20:53   #43
Registered User
 
Celestialsailor's Avatar

Join Date: Nov 2006
Location: In Mexico, working on the boat
Boat: Hallberg Rassy 35. and 14ft.Whitehall pulling skiff.
Posts: 8,013
Images: 5
Re: Broken Rocker Arm Shaft Mounts

Quote:
Originally Posted by jimbunyard View Post
Sounds to me like a basic synopsis, no blame inferred. When I get on a boat I'm unfamiliar with, I don't leave until I'm confident in its' ability. The captain is responsible for the boat, the owner is responsible for the bills for running the boat.







Celestial Sailor, Good job, god. Wish I had your all-knowing prescience.
Your little reverse psychology bs means nothing other than "yeah for our side". What you didn't attach speaks volumes as to trying to "win" your way to pointless position. The OP stated first he didn't adjust the valves then a few posts later...of course I adjusted the valves. So if your little sly stab of "Wish I had your all-knowing prescience", then I wish you had so some knowing prescience to put 2=2 together.





Feeling a little guilty? Good. Rant all you want. The introductory post states very clearly that the OP bought a boat and arranged for someone to deliver it to him. Since we can't know if the owner told the captain that the boat was competent to make the trip, the worst case is to assume that he didn't. If that is so (and actually, even if he did say it was competent), the responsibility is on the skipper to make sure that the boat could survive the trip, if only in the interest of self-preservation. If he didn't, and the worst thing that happened is he burned up the engine, he should consider himself lucky, and, as appears to be the case, hope that the owner doesn't hold him responsible in some way. (Assume I'll get some flack on that one though...)
Why would I feel guilty about pulling someones covers while trying to blame someone for his inability to make sure all was in order. I make the point again. All good installations have temp. alarms. You conveniently avoided that little detail.

Of course, it seems a moot point, since it doesn't appear he's coming back. Again, good job, experts.
...and again...yeah for our side.





Always nice to hear some calm good sense.
My so called rant was to bring awareness to the op of taking responsibility for his boat. Not merely responsible for the bills of his vessel. One of the more stupid statements you've come up with.
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: Wow - what a ride!"

http://wwwjolielle.blogspot.com/
Celestialsailor is offline   Reply With Quote
Old 14-11-2015, 00:46   #44
Registered User

Join Date: Nov 2013
Location: Slidell, La.
Boat: Morgan Classic 33
Posts: 1,105
Re: Broken Rocker Arm Shaft Mounts

Quote:
Originally Posted by Celestialsailor View Post
My so called rant was to bring awareness to the op of taking responsibility for his boat. Not merely responsible for the bills of his vessel. One of the more stupid statements you've come up with.
Always love being called stupid. (oh, and by the way you (f you remember) called it a rant...


Also, by the way, what exactly didn't I attach? If I were (as you so memorably put it) pulling out my blame throwers, I wouldn't be so coy as to leave that out...


And please, don't answer, or, if you do, don't expect a reply....
__________________
jimbunyard is online now   Reply With Quote
Old 14-11-2015, 06:27   #45
Moderator
 
HappyMdRSailor's Avatar

Cruisers Forum Supporter

Join Date: May 2008
Location: North Mississippi
Boat: 48 Wauquiez Pilot Saloon-C22 Chrysler Sunpiper- 19 Potter-Preparing to cruise w/my girl
Posts: 5,980
Re: Broken Rocker Arm Shaft Mounts

Seriously guys... Cut the crap...

None of this has anything to do with the OP's actual question...

"Why did this happen?"

I suggest that some of the replies could have been put in a more polite manner... And the heated debate was completely unnecessary...

The OP has 7 posts total, six here and one more OP that didn't even get one answer... If the goal was to chase of a new inexperienced vessel owner looking for help... I tend to think WE ALL just might have succeeded...

If the OP EVER comes back, our answers should be positive, direct and helpful...
__________________

__________________
In the harsh marine environment, something is always in need of repair...

Mai Tai's fix everything...
HappyMdRSailor is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Through Hull-Valve Broken or Not-Broken? Jado27 Monohull Sailboats 15 16-03-2016 07:14
After market engine mounts and polymer mounts Rustic Charm Engines and Propulsion Systems 32 10-03-2015 02:13
Want To Buy: Gusher 8 Mark III Rocker Arm butch Classifieds Archive 4 15-06-2014 20:45



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 00:45.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.