Rebuild Perkins Diesel

Aug 7, 2022
17
Custom Declercq 51 Green Bay
I should add that when the boat was originally built there was an access hatch in the cockpit that provided access to remove the engine. During a refit about 30 years ago the hatch was removed and replaced with a solid cockpit sole.
I am looking at purchasing 51ft Declercq. Engine runs fine however for long term will need to be rebuilt. The problem is access. Unlike most production boats the engine is accessible from both sides and the top not from the front. Is it possible to tear the engine down on the mounts and then after cleaning etc reassemble on the mounts?
 
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Jan 4, 2006
7,230
Hunter 310 West Vancouver, B.C.
Engine runs fine however for long term will need to be rebuilt.
Unusual statement. Why do you thing it needs rebuilding ? What is the scope of work ?

We will need the following info to make an intelligent guess about this project:

Engine make and model.
Age of engine.
And most important, the running hours.
 

RoyS

.
Jun 3, 2012
1,742
Hunter 33 Steamboat Wharf, Hull, MA
Would you be able to work under the engine to access the piston connecting rods and the crank shaft?
 

leo310

.
Dec 15, 2006
646
Catalina 310 44 Campbell River BC
Remember if its running fine then what's the problem? Think about this if its hours that you think is why the rebuild is required, if you drive 2.5 hours to work then your putting on over 5000 hours per year so do you rebuild your engine every year?
 
Jan 4, 2006
7,230
Hunter 310 West Vancouver, B.C.
That is one helluva commute.
That was originally what I thought. But when I took a second look at the figures, figuring around 48 weeks/ year of work days, that's pretty close to my 10 mile each way, daily commute (by car), back when I prostituted myself to the trade. What a waste of time.
 
Aug 7, 2022
17
Custom Declercq 51 Green Bay
Hours are unknown, engine is 40 years old however it does run very good. Long term intent is to retire in 3 years and take the boat on circumnavigation. My concerns are the age and the unknown hours. Boat has made 2 longer trips in lifetime, 1 to Bahamas, and a second that was year long trip to southern Caribbean and back to Wisconsin.
 
Aug 7, 2022
17
Custom Declercq 51 Green Bay
Would you be able to work under the engine to access the piston connecting rods and the crank shaft?
I would not be able to work under the block. I would need to raise the engine some in order to drop oil pan and get to the crankshaft, connecting rods etc.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,961
CAL 35 Cruiser #21 moored EVERETT WA
Which Perkins is in the Boat.
If it is a 4.107 or 4.108, Buy the boat.

Repower with a brand new Beta. It will make your open water passage sailing safe and rewarding.

Send me the old Perkins, I'll pay shipping and you'll know the engine went to a good home.
WIN WIN>>..
 
Aug 7, 2022
17
Custom Declercq 51 Green Bay
Which Perkins is in the Boat.
If it is a 4.107 or 4.108, Buy the boat.

Repower with a brand new Beta. It will make your open water passage sailing safe and rewarding.

Send me the old Perkins, I'll pay shipping and you'll know the engine went to a good home.
WIN WIN>>..
It is a Perkins 4-236.
I am trying not to eat the cost of a brand new engine
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,961
CAL 35 Cruiser #21 moored EVERETT WA
That one shouild be decent for a 51 foot boat of say 30,000 pounds displacement. The 4.107 moved my boat at hull speed 7.2 knots when going 90% RPM. Loaded I figure I have a boat of 18,000 lbs.
 
Aug 7, 2022
17
Custom Declercq 51 Green Bay
That one shouild be decent for a 51 foot boat of say 30,000 pounds displacement. The 4.107 moved my boat at hull speed 7.2 knots when going 90% RPM. Loaded I figure I have a boat of 18,000 lbs.
Boat weighs 40,000. The engine still moves her without issue. I'm not certain what top speed would be however she easily makes 6 knots on engine.

My decision is whether I should rebuild, replace or wait and see what transpires over the next few years.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,961
CAL 35 Cruiser #21 moored EVERETT WA
It made sense to me to practice good maintenance. Cruise the boat and fear not using the engine in known waters. Sails are my primary mode of power. When coming into port the auxiliary powers the boat in tight quarters. I also have tow insurance so if a problem comes up it is possible to call for help.

When planning a cruise to unfamiliar waters and remote anchorages having a reliable auxiliary engine was a priority. My engine rebelled and quit on me in my home port. Not in foreign waters. Now it is a decision among several options.

I would give it time until you feel uncomfortable about the situation then act based on the data presented. If I can find a decent rebuild or if mine is rebuild able at a fair cost that is my probable path. If not a Beta Marine looks like a good option.
 

RoyS

.
Jun 3, 2012
1,742
Hunter 33 Steamboat Wharf, Hull, MA
Is there an obstruction that prevents you from pulling the engine out of your boat? If not, then IMHO you will be much better off rebuilding it on a bench in your basement. Take the transmission home as well (still attached) and replace the shaft seals.
 
Apr 5, 2009
3,106
Catalina '88 C30 tr/bs Oak Harbor, WA
You indicated that the engine access to place it into the boat was a hatch above which has been glassed over. As you stated, you will need to life the engine to access the pan and crank. You may need to consider drilling a hole through the sole over the engine to mount a picking point so that you can raise the block with a tackle or come-a-long. If you size the hole for an eyebolt, you can patch the hole by inserting a carriage bolt sealed with your favorite flavor of sealing goo.
 
Aug 7, 2022
17
Custom Declercq 51 Green Bay
Is there an obstruction that prevents you from pulling the engine out of your boat? If not, then IMHO you will be much better off rebuilding it on a bench in your basement. Take the transmission home as well (still attached) and replace the shaft seals.
It will be very difficult to pull the engine due to access. I won't say it can't be done however I am not sure how it can be done
 
Aug 7, 2022
17
Custom Declercq 51 Green Bay
You indicated that the engine access to place it into the boat was a hatch above which has been glassed over. As you stated, you will need to life the engine to access the pan and crank. You may need to consider drilling a hole through the sole over the engine to mount a picking point so that you can raise the block with a tackle or come-a-long. If you size the hole for an eyebolt, you can patch the hole by inserting a carriage bolt sealed with your favorite flavor of sealing goo.
If I understand you correctly I could drill a hole in the cockpit sole, lift the engine with a chain through the hole. I could then work on it while it's hanging or work it out the side access hatches and then through the hatch to work on it in the garage.
 
May 25, 2012
4,338
john alden caravelle 42 sturgeon bay, wis
if i were you, i might call al declercq, the designer's son and highly skilled sailor, sailmaker. top pro sailor for the last 50 years

declercq llc. st clair shores michigan. quantum sails detroit, ask for AL

see what he might know. prolly knows a lot about that boat.

where is the boat?
is the boat on lake st. clair?
he is a friend. also sold me almost all my sails for all my boats. i winter in toledo but sail out os sturgeon bay all summer.


P.S. i'm just quessing that your boat was designed by al's dad. who did design boats. and was from detroit and the boat's in detroit
 
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Aug 7, 2022
17
Custom Declercq 51 Green Bay
if i were you, i might call al declercq, the designer's son and highly skilled sailor, sailmaker. top pro sailor for the last 50 years

declercq llc. st clair shores michigan. quantum sails detroit, ask for AL

see what he might know. prolly knows a lot about that boat.

where is the boat?
is the boat on lake st. clair?
he is a friend. also sold me almost all my sails for all my boats. i winter in toledo but sail out os sturgeon bay all summer.


P.S. i'm just quessing that your boat was designed by al's dad. who did design boats. and was from detroit and the boat's in detroit
Email me at redlegmsg66@outlook.com