Reply
 
Thread Tools Display Modes
 
Old 08-31-2013, 08:47 AM   #21
Ben
Guru
 
Ben's Avatar
 
City: Wilmington, NC
Country: US
Vessel Name: Sand Castle
Vessel Model: 1986 MT Sundeck 35.5
Join Date: Dec 2007
Posts: 693
I have an American Diesel 136N which is a modified Ford Lehman diesel similar to the SP135. I don't know how much rattling is "too much", but mine too, has a rough idle at 1000 and below RPMs when cold. It rattles the galley dishes and stove grills. I might be due for an injector exchange, but boat has been running like a champ. I've got about 5000 hours.
__________________
Advertisement

__________________
..................................
Ben

MV Sand Castle
Wilmington, NC
Ben is offline   Reply With Quote
Old 08-31-2013, 12:28 PM   #22
Guru
 
Forkliftt's Avatar
 
City: Biloxi Mississippi
Country: USA
Vessel Name: Patricia Louise II
Vessel Model: 1983 42' Present Sundeck
Join Date: Oct 2007
Posts: 2,433
Quote:
Originally Posted by Brooksie View Post
Good thought, narrow it down to one or the other engine; then, if owner will allow, loosen injector lines one at a time with that engine idling to find the offending cylinder (it's the one where the idle doen't get rougher when loosened). Then swap in an injector from the smooth engine to that cylinder. If then the engine idles correctly, you had a bad injector. If not you have a compression issue (valves maybe). Above is 1 hours work for a mechanic.
Great approach, I know the 135 Lehmans are a pretty big deal to swap.
__________________

__________________
Steve Point Cadet/ Biloxi, Mississippi USA
*Present 42 twin 135 Lehmans
Forkliftt is offline   Reply With Quote
Old 08-31-2013, 12:49 PM   #23
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 15,908
Quote:
Originally Posted by Forkliftt View Post
Great approach, I know the 135 Lehmans are a pretty big deal to swap.
When I had t get water out of my cylinders...the mech felt he had to take the rocker arm off my 120 to get to the injectors...not sure now if that's necessary but if it is, not an hour task....

anyone pull the injectors on a 120 and NOT have to remove the rocker arm?
psneeld is online now   Reply With Quote
Old 08-31-2013, 01:45 PM   #24
Veteran Member
 
JESSEDIVER49's Avatar
 
City: Houston
Country: USA
Vessel Name: Good Vibrations
Vessel Model: Grand Banks Classic 42
Join Date: May 2013
Posts: 90
Rough Idle on GB 42 - Ford Lehmans

I do appreciate all the great inputs on this issue. I'm now off the fence and plan to move forward with the purchase.

JESSEDIVER49
JESSEDIVER49 is offline   Reply With Quote
Old 08-31-2013, 05:30 PM   #25
Senior Member
 
Adelaide's Avatar
 
City: La Conner, WA
Country: USA
Vessel Model: 1983 Tung Hwa Clipper
Join Date: Sep 2011
Posts: 365
Quote:
Originally Posted by JESSEDIVER49 View Post
I do appreciate all the great inputs on this issue. I'm now off the fence and plan to move forward with the purchase.

JESSEDIVER49
Enjoy your new boat congrats!
Adelaide is offline   Reply With Quote
Old 09-02-2013, 02:54 PM   #26
Guru
 
hmason's Avatar
 
City: Westport, CT
Country: USA
Vessel Name: Magic
Vessel Model: Grand Banks 46 Europa
Join Date: Aug 2013
Posts: 1,904
Call Bob or Brian Smith at American Diesel in Kilmarnock, VA. NOBODY knows more about the Lehman than this father and son team. They are the source of parts and information and are always pleased to talk about their Lehman engines. Good luck.
hmason is online now   Reply With Quote
Old 09-24-2013, 11:07 AM   #27
Member
 
counterpoise's Avatar
 
City: Ft Lauderdale, Fl.
Country: USA
Vessel Name: Counterpoise
Vessel Model: 1980 Bristol 42 Trawler
Join Date: Mar 2012
Posts: 8
My 120's at low idle set up harmonics that vibrate everything... They do not idle rough. Just the vibration from the engines....just love em!
David
counterpoise is offline   Reply With Quote
Old 09-24-2013, 01:58 PM   #28
Guru
 
River Cruiser's Avatar
 
City: UMR MM283
Country: US
Vessel Name: Northern Lights II
Vessel Model: Bayliner 3870
Join Date: Jan 2013
Posts: 1,228
One thing that will cause a loud rattle at idle is a worn drive plate, usually a small increase in rpm & it will stop.
__________________
Ron on Northern Lights II
I don't like making plans for the day because the word "premeditated" gets thrown around in the courtroom.
River Cruiser is offline   Reply With Quote
Old 09-24-2013, 07:24 PM   #29
Guru
 
Xsbank's Avatar
 
City: Pender Harbour, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 2,447
Taking off the valve train is just running up your bill...

Try and warm your engines at 1000+ rpm or better yet, in gear!

1 service your injectors at 1200 hours or when there is too much fuel and smoke in the water. "Too much" is for you to figure out.
2 adjust your valves too
3 torque your head bolts
4 change Simms pump oil at 50 hours without fail. Ziplocks are useful for this
5 install the American Diesel coolant tank very soon
6 burp the coolant valve on top of the block
7 check the raw water impeller and replace annually
8 buy a dozen heat exchanger zincs and a couple of caps and check them regularly
9 buy a new transmission cooler, install it and keep the old one for a spare
10 if you have an oil leak, it is 99% likely it's the lift pump gasket, even though it looks like it's the valve cover etc. Buy one and put it on and keep the old one for a spare.
11 toss the Simms pump drain tube, plug the hole and drill a small hole in the filler cap. This will stop a lot of mess.
12 likely, your dipstick will be marked wrong - measure the oil you put in then remark the stick
13 probably your engines and shafts are due for alignment - it's not hard but it will make everything smoother. Everything.
14 change the on-engine fuel filters unless you know for sure when they were done
15 if your drive-coupler plates rattle, they are shot and need changing. They won't fix themselves
16 never shift gears except at idle. Never.
17 change the oil in your transmission(s) too - it will make you happy.
Xsbank is offline   Reply With Quote
Old 09-24-2013, 07:27 PM   #30
Guru
 
Xsbank's Avatar
 
City: Pender Harbour, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 2,447
The rattle of a Lehman is the best way to tell its running.
Xsbank is offline   Reply With Quote
Old 09-24-2013, 08:35 PM   #31
Guru
 
Xsbank's Avatar
 
City: Pender Harbour, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 2,447
I meant to say fuel in the water, not oil - Marin corrected me.

I did mean to say that you should re torque the head bolts. I know this is only "required" on the turbo versions, however many of these engines are nearing 50 years old, they are rarely owned by the original owner, therefore many have been opened up and otherwise rebuilt or messed about with. The manual clearly calls for retorquing after the head has been off, after a few hours use, but many people do not do this task. Therefore, unless you have clear documentation that this has been done, a new owner should do this easy task. All it does is prevent an unnecessary head gasket failure...

The Lehman is basically such a simple, reliable engine, if it's running now it will likely continue to run for some years (given a heavy user might be 300 hours annually?) and give you lots of warning before it fails, therefore a feckless owner may not touch it until it blows. I happen to think that you should be kind to your engine, especially if you only have/had one and my little list is what I would do/have learned from babysitting one.
Xsbank is offline   Reply With Quote
Old 09-24-2013, 10:16 PM   #32
Senior Member
 
Join Date: Feb 2012
Posts: 134
XSbank, that's one of the best written simple basic service procedures I have seen, thanks.
expat is offline   Reply With Quote
Old 09-24-2013, 11:19 PM   #33
Guru
 
SomeSailor's Avatar
 
City: Everett, WA
Vessel Name: Honey Badger
Vessel Model: 42' CHB Europa
Join Date: Oct 2011
Posts: 784
Mine are the same. Rattles at 600-800 RPM. Smooths out at 1000 or so and above. You learn what things need a strategic rag stuffed behind them.
SomeSailor is offline   Reply With Quote
Old 01-28-2014, 10:22 AM   #34
Newbie
 
City: Powell River
Country: Canada
Vessel Name: Griz
Vessel Model: Perma-Glas
Join Date: Jan 2014
Posts: 3
I recently purchased a 38' Permaglas trawler that has a 120HP Lehman and the engine runs rough below 1000 rpm. Would it cause a problem to run the engine for long periods of time below 1000 rpm or is there a solution to make it run smoother. Would like to be able to troll for salmon! Thanks.
Rheal is offline   Reply With Quote
Old 01-28-2014, 11:54 AM   #35
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 3,888
There are more than one kind of rough: One is from an engine problem like a misfire where not all six are hitting evenly. That's like a lump every six pulses. Engine in that case will sound uneven.

The other kind of rough is normal at low revs: The engine fires three times per rev, and each fire gives engine a shake. Lower revs make it more pronounced. If the mounts are stiff, this normal shake gets transmitted into hull structure and runs around the whole boat.

If your engine is running fine, but has low rpm shake getting into the boat, it does not really hurt anything, just annoying.

The fix is softer mounts. I have set up several with Barry mounts (the ones used on smaller Cummins) and they work very well. Soft enough to isolate vibes down to 5-600rpm, but stiff enough to keep alignment intact. Metallastic is another good mount, often seen on Volvos.

Swapping mounts is sometimes easy, but often the brackets and holes are not such that a direct swap can be made. New brackets, etc may need to be fab'd.

Mounts also must be very carefully selected. Each has a load rating and you have to match that so engine "floats". If weight per mount is estimated wrong, or wrong mounts selected, the mount will go beyond its limit of travel one way or the other and the engine won't "float". Vibes then still go through.

Done right, the improvement is remarkable.
Ski in NC is offline   Reply With Quote
Old 01-30-2014, 07:40 AM   #36
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 16,530
Here (SW FL) most injector shops will check injectors for free or about $5.00 each.

Rebuilding is in the $60 -$75 range each.

Removal and replacement is a low skill no problem task.

With the age of the engine rebuilt injectors would be required anyway.

However checking the valve adjustment should be done first .

If that doesnt smooth the idle , pull the injectors , check the compression , and have the injectors rebuilt.

With OK compression , if new injectors does not smooth the beast , the injection pump will need to be next to check.

The injection pump R&R can be complex , depending on the engine as re-timing may be needed..
FF is offline   Reply With Quote
Old 01-30-2014, 08:36 AM   #37
Guru
 
City: Fort Myers
Country: USA
Join Date: Jul 2013
Posts: 956
This alone should be a sticky for all to know/follow, great stuff:
Quote:
Originally Posted by FF View Post
Here (SW FL) most injector shops will check injectors for free or about $5.00 each.

Rebuilding is in the $60 -$75 range each.

Removal and replacement is a low skill no problem task.

With the age of the engine rebuilt injectors would be required anyway.

However checking the valve adjustment should be done first .

If that doesnt smooth the idle , pull the injectors , check the compression , and have the injectors rebuilt.

With OK compression , if new injectors does not smooth the beast , the injection pump will need to be next to check.

The injection pump R&R can be complex , depending on the engine as re-timing may be needed..
Marlinmike is offline   Reply With Quote
Old 01-30-2014, 10:53 AM   #38
Senior Member
 
City: Gig Harbor
Country: USA
Vessel Name: Selah
Vessel Model: Ocean Alexander 40
Join Date: Dec 2011
Posts: 191
Ski
I changed mounts on one engine last year and I'm about to do the other. A PN and supplier for the Barry mounts for a FL 120 would be appreciated.
av8r is offline   Reply With Quote
Old 01-31-2014, 12:34 PM   #39
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 3,888
Quote:
Originally Posted by av8r View Post
Ski
I changed mounts on one engine last year and I'm about to do the other. A PN and supplier for the Barry mounts for a FL 120 would be appreciated.
Link to Barry: Barry Controls | Specialty Isolators | Marine Engine Mounts

There are downloads for the mount spec sheets. Need to know weight per mount. 27391-3 pretty typical for total engine and gear weight of 1400-2000lb. The smaller one is also useable on smaller engines.
Ski in NC is offline   Reply With Quote
Old 01-31-2014, 08:21 PM   #40
Guru
 
Xsbank's Avatar
 
City: Pender Harbour, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 2,447
Gentlemen, Lehmans rattle somewhere below 1000 r/m. If you are ever at a GB Rendezvous, when all the old dears start up on Sunday morning, not only can you not see your neighbour for the smoke but you had better have already said your goodbyes as the noise is, well, interesting.

You can do your injectors and adjust your valves and do your engine mounts and there will be some improvement but you will still have to pad up the Waterford and the bone China. Just increase the r/m until it stops. That's it.
__________________

Xsbank is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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





All times are GMT -5. The time now is 04:56 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012