Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 25-06-2017, 18:13   #1
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Rebuilding Westerbeke W30, aka 4-91

In the process of rebuilding a Westerbeke W30, vintage 1979 or so. Planning on documenting the work here as it progresses. I am a mid level wrencher, have done lots of external stuff on engines, have parted out a couple of marine diesels, but only internal engine work was replacing the piston and cylinder on my motorcycle last fall which gave me the confidence to move forward with this, my first major rebuild. I figure, why not start with a rare obsolete foreign engine for a beginner. Westerbeke prices are a major deterent, eg $341 for just a head gasket.

I have done my homework on this engine, it is a British Motor Company B-series variant. Gas version used in tons of well known cars, MGA's and Nash Metropolitans in particular. I have purchased as much stuff as I need so far from Moss Motors, Brit sports car specialists. Great website with diagrams and tech tips, majority of which apply. Diesels parts interchange with Leyland 154 tractors and remain popular in the English narrowboats so there are alternate sources.

Started off with an engine from craigslist. Seller only spoke Spanish, so I had one of my Latina friends contact him. Got only limited info about it, but said it ran and only wanted $400. Drove to Miami and picked it up. Was running when I arrived. Usually not a good sign. No cooling water and a strait exhaust, made it hard to tell much, but did not smoke excessively and seemed OK.

Dragged it home and it has sat in the garage for 3 years awaiting my attention. Finally pulled it out and tore it down. Not bad overall, worn as expected, but nothing catastrophic. Couple of broken piston rings (may have been me), worn journals, etc. Just a tired old engine. Showed it to a gearhead friend who thought it looked feasible.

Looked around and made a few calls to machine shops. Found one with no website, don't take credit cards, the owner was an older guy who answered the phone himself and was very encouraging. Perfect. Took it in, he looked it over, confirmed my pistons were shot and it needed rebored, and gave me a ballpark of $550 for machining. Thought the crank was probably OK. There is a tractor supplier that has a complete rebuild kit with new stock size pistons and sleeves for $1100, but he said that the labor of resleeving was high. Only stumbling block was the cam bearings which were worn but usable. The original bearings are a "semi-finished" split design which are installed, then finish honed in place. Special tool required, no longer available of course, so that's a no-go. He sent me home and told me to bring it all back when I have new pistons in hand. I got a set of NOS .030 over pistons on eBay, came from Cyprus in just a week, for $387. More homework revealed a fully finished solid cam bearing set available for $30. Turns out the hot tanking process destroys the existing bearings anyway.

Took it all back, dropped off the spec sheet, a week later it is all done. Block hot-tanked, bored and honed, crank needed attention-main and rod journals reground .010 over, head resurfaced/valve work all done, one con rod needed to be reconditioned, cam bearings installed, everything all checked for cracks, etc. $780 with tax which seems very fair to me. Never got the feeling he was trying to "upsell" me.

Got it home, mounted block on engine stand. This was a bit tough as the thing is designed for a bigger block, but I hade it work with 3 of the 4 arms.
Cleaned the crank, shot brake cleaner on journals and thru all the oil passages to clear out any residual grinding debris. Block cleaned with brake fluid in oil passages, tappets holes, etc as well, then with detergent and water in cylinders until cloth comes out clean, followed immediately with WD40 to prevent rust. Brake cleaner then WD40 on cam bearings.

Prep work all done, ready to begin.
Attached Thumbnails
Click image for larger version

Name:	IMG_4230.jpg
Views:	100
Size:	418.1 KB
ID:	150687  
__________________

__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 25-06-2017, 18:29   #2
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

First step was to replace the flywheel bolts in the crankshaft. These had to be removed for machining. Machinist suggested tapping them in with a drift, but with the counterbalance, there's no room. I pressed them in with a C clamp, towel protecting the journal.
Attached Thumbnails
Click image for larger version

Name:	IMG_4231.jpg
Views:	653
Size:	421.3 KB
ID:	150688  
__________________

__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 25-06-2017, 18:35   #3
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

Interesting detail on this old engine. There is no rubber rear seal. I was always baffled at not being able to find the rear seal in the parts book. It has what's called a scroll seal. The crankshaft fits very closely with in the block behind the rear main bearing. The crank has a spiral groove cut in it that draws any oil leaking past the bearing back into the block. It almost works well.
Attached Thumbnails
Click image for larger version

Name:	IMG_4232.jpg
Views:	649
Size:	397.7 KB
ID:	150689  
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 26-06-2017, 10:54   #4
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2013
Location: Oregon to Alaska
Boat: Wheeler Shipyard 83' ex USCG
Posts: 1,908
Re: Rebuilding Westerbeke W30, aka 4-91

Wd-40 is useless as a water proofer. WD will expell water, but provides almost no protection. WD = water displacement and is designed to dry wet electrical parts. It has almost NO oil. If it did, after use, breakers, etc., would combust. Oil or grease is a better protector of machined metal.
Use some type of assembly lube on the bearings and other wear points. The lube is dissolved into the oil on 1st start. If nothing else, use grease instead of WD-40.
If possible, pressurize the oil before starting. A drill driving the oil pump, or an electric pump. The point is to fill the oil passages so after starting 1st oil pressure comes faster.
Lepke is offline   Reply With Quote
Old 26-06-2017, 13:31   #5
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

Washed with detergent and water... then WD40 to prevent rust. WD40 gets the water out, dry steel does not tend to rust like wet. There is enough oil in it to keep it OK til the pistons are ready to fill the holes.
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 29-06-2017, 10:55   #6
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

I got the crankshaft in last night. Initially torqued it down with green Plastigage to check clearance. Looked okay so I disassembled, re-cleaned, and reassembled everything after generously applying assembly lube to all bearing surfaces. Sequentially torqued the main bearing caps, checking that crank turned easily without binding after each one. Last task of the evening- I assembled the new pistons onto the old connecting rods, carefully checking that they were numbered to go in the correct cylinder. New Circlips included with pistons and rings came pre-installed. Ready to go into the holes next.
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 29-06-2017, 12:15   #7
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

Bearings in, btw these are MGA bearings from Moss, (King brand which the machinist said were top notch), $32 each set for mains and big ends. Regular aftermarket were $12 or so
Attached Thumbnails
Click image for larger version

Name:	IMG_4238.jpg
Views:	119
Size:	408.7 KB
ID:	150903  
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 29-06-2017, 12:18   #8
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

Plastigage is a little plastic thread that squishes down accurately to measure clearance. Available at auto parts store. This shows about .001 width.
Attached Thumbnails
Click image for larger version

Name:	IMG_4239.jpg
Views:	94
Size:	397.3 KB
ID:	150904  
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 29-06-2017, 20:05   #9
Registered User

Join Date: Nov 2013
Location: Slidell, La.
Boat: Morgan Classic 33
Posts: 1,368
Re: Rebuilding Westerbeke W30, aka 4-91

Quote:
Originally Posted by sanibel sailor View Post
I got the crankshaft in last night. Initially torqued it down with green Plastigage to check clearance. Looked okay so I disassembled, re-cleaned, and reassembled everything after generously applying assembly lube to all bearing surfaces. Sequentially torqued the main bearing caps, checking that crank turned easily without binding after each one. Last task of the evening- I assembled the new pistons onto the old connecting rods, carefully checking that they were numbered to go in the correct cylinder. New Circlips included with pistons and rings came pre-installed. Ready to go into the holes next.
Just out of curiosity, can you describe 'sequentially' in more detail? It's interesting to see the subtle differences people perform to achieve the same result...
jimbunyard is offline   Reply With Quote
Old 30-06-2017, 03:12   #10
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

I don't know if there is a "right" way. Not detailed in tech manual or MGA websites I am using. I snugged with ratchet which was roughly 20 ft/lb, then with torque wrench to 40/60/75, checked for ease of turning after each. Started with center cap, then front, rear last.
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 30-06-2017, 03:28   #11
Registered User

Join Date: Nov 2013
Location: Slidell, La.
Boat: Morgan Classic 33
Posts: 1,368
Re: Rebuilding Westerbeke W30, aka 4-91

That it's not in the service manuals, that I've seen either, is why I asked...I do it exactly the same way, sequence and torqueing schedule, but use both oil and assembly lube. Don't ask me why, just always done it that way...
jimbunyard is offline   Reply With Quote
Old 30-06-2017, 06:01   #12
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

I just used assembly lube. Given my pace, it may be a good long while before completion and regular oil is more likely to flow out of bearings.
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 01-07-2017, 15:24   #13
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

Got the #1 piston in, oiled and used the ring compressor and it slid right in. Ran into first snag. The con rod bearings are not the right size. The MGA has considerably smaller crankpins than the diesel. I had checked the mains,thought I had checked the big end dimensions also, but I guess not. Need to talk to the tractor suppliers. Head gasketis not quite right either, so I may pick one of those up rather than trying to enlarge the cooling passages on the one I have.
__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Old 04-07-2017, 14:19   #14
Registered User
 
CS Cruiser's Avatar

Join Date: Mar 2013
Location: PCYC Toronto
Boat: CS36T
Posts: 311
Images: 10
Re: Rebuilding Westerbeke W30, aka 4-91

Thanks for posting John, have the same W30 and I'm sure the day will come for my rebuild as well.
__________________
Paul
s/v TENACITY - CS36T
CS Cruiser is offline   Reply With Quote
Old 04-07-2017, 15:50   #15
Registered User
 
sanibel sailor's Avatar

Join Date: Feb 2013
Location: Sanibel FL
Boat: 1979 Bristol 35.5 CB
Posts: 981
Re: Rebuilding Westerbeke W30, aka 4-91

Had 2 bad glow plugs which I was able to cross reference and find on ebay for $12 each shipped. Better than $200 from Westerbeke.

SINGLE CORE BMC ENGINES 1.5 1.8 2.5 (DIESEL) DIESEL GLOW PLUG CH32 -GPS302X1 | eBay
__________________

__________________
John Churchill Sanibel FL
NURDLE, 1979 Bristol 35.5 CB
sanibel sailor is offline   Reply With Quote
Reply

Tags
westerbeke, rebuild

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
Westerbeke W30/4-91 Idle Screw Assembly/An Engine for Parts Reklobe Engines and Propulsion Systems 8 01-06-2017 19:52
NEMA 2000 Data from Westerbeke W30 4-91 SS Little-Devil Engines and Propulsion Systems 13 25-08-2012 08:08
Westerbeke w30 occasionally over revs mlydon Engines and Propulsion Systems 4 22-05-2012 13:52
For Sale: Westerbeke W30 Parts The Way Classifieds Archive 24 16-05-2012 05:46
Westerbeke W30 Raw water pump stevec195 Engines and Propulsion Systems 5 09-05-2012 16:25



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 05:48.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.