KUBOTA MATERIALS PURCHASED

The problem started during our cruising in the Florida and Bahama waters. Our raw water pump started to leak, which is more serious in salt water conditions as it quickly corrodes the surrounding area of the engine. We replaced seals on the pump but were not successful in stopping the leaking. We purchased a new pump from a dealer in the Annapolis MD area , had it shipped to Canada , and after several months , arrived at the boat to find that the pump was slightly different and obviously for a different engine . We tried to return the pump but the company was out of business. We were able to use some parts of the pump including the impellor. After installing the new impellor, and running the engine for several hours, we had a complete failure of the impellor. All the blades except for two, broke off. (We believe the pump had been stored for many years in extreme heat) We had an immediate major overheating of the engine, even though we had an audible warning on the engine. We found the problem, replaced the impellor and continued cruising. Unfortunately the overheating had warped the #3 cylinder exhaust valve at the rear of the engine and cracked the head. Neither of these problems were evident until several years later when we stared to hear very sharp popping sound from the exhaust and difficulty in starting. We brought the boat back to Canada in 1999 and cruised Georgian Bay , but by the end of the summer , it was evident that we would need to do work on the engine. At this point I believed it was a burnt valve.

This spring I removed the head and saw immediately that the exhaust valve on #3 cylinder was burned . To determine how badly, I poured Varsol into the exhaust ports of the three cylinders, #1 and #2 did not leak, Varsol poured past #3 cylinder exhaust valve. I borrowed a valve spring compressor from Canadian Tire and removed the valves from #3 cylinder. The face of the exhaust valve was completely burned away .

I felt that grinding the seat and replacing the valve was possible, not realizing that the head was cracked. There was no visible evidence of a crack in the head. I took the head to a machine shop who advised me that the head was cracked and would need to be welded or replaced. He suggested that all the parts would need to come from Westerbeke. Welding the head was to cost $700.00 , plus , the associated parts that were necessary for the cost of $1200. and he said told to " not hold him to that price" he said a new head would cost me $3000.00 He said a new head gasket set would cost $500.00. He subsequently said that the gasket set would only cost me #300.00 but would have trouble figuring out what model Kubota engine it was. I told him not to do anything more. I paid him $136.00 which I felt was a fair price for the two hours labour to inspect the head.

We found the 5424 was actually a DH 1101 ( through the information in the Aloha 34 newsletter) I went to my local Kubota dealer and ordered all the parts mentioned above for $2102.08 (without taxes) Parts arrived in about 5 days.

I borrowed the valve spring compressor from Canadian Tire once again, and installed the valves and checked the specs on the valve and piston clearance .(which was fine) This took a couple of hours . I took all the parts to the boat, and spent about four hours with a little help from a friend and installed the head, and torqued the head bolts to specifications, installed the exhaust manifold, intake manifold and the part that covers the front part of the head.

On another day, I installed the pushrods, rocker arm, and set the valve tappets at .008 thou . I had to make one gasket for the back of the exhaust manifold as it was not available. I had some trouble with two studs that had the nuts frozen on them. In one case with the 3 " stud holding the manifold, I was able to cut the stud down and still use it. The other one, I simply screwed back in with the nut still rusted on it. (this was on the back of the exhaust manifold)

The time mentioned above does not include, literally hours, trying to find gasket material, trying to find studs, trying to find the right hoses .( I changed all of the water system hoses and the return hose on the injectors) I had to purchase a socket to install the injectors.( a deep 1 1/16 standard )

We have just arrived home from the boat after spending approximately 4 hours getting the engine started. We had difficulty in getting fuel to the injectors for some reason. Also, because the boat is on the hard, we had a devil of a time getting the raw water pump to lift water out of a pail( air locks in the system) We have a Sea Frost compressor- driven refrigeration unit which makes the pump much more difficult to prime. If I was installing the Sea Frost again, I would install the condenser in a different location.

Once we got the engine started, it ran beautifully . Slight noise from the tappets, but we only ran the engine for about 15 minutes, just to make sure everything was working well. After we launch, I will run the engine for approximately an hour, and then re-torque the head bolts, and set the valves. may set them at .007 thou instead of .008 thou according to the sound of the engine after an hour of running ( the specs are .007 to .009 thou)

This is a job that anyone with a reasonable amount of mechanical ability could do if they are careful and take their time. The shop manual and parts list are extremely important and I can’t thank Migs enough for the help he provided for getting us all the information on the engine. Not only did I save myself money by doing the job myself but I had a lot of fun doing it. Thanks again Migs.

Last updated  13 January, 2006 - © Aloha Owners Association