Replacing the drive belt on our Universal M25-XP
Our Universal M25-XP Diesel Engine on Eximius our 1987 Catalina 34 is probably 35 years old, it may have been built a couple of years before that. In the 8 years that we have owned Eximius, we have gone through just a few drive belts, but we have had to put up with the Squealing of the belt when the electrical system requested a lot of power from the Alternator and the 'Belt Dust' that is shed over the engine despite the frequent checking of the alignment of the pulleys that are driven courtesy of the Drive -V- Belt.
Over the past year, we have made substantial upgrades to our electrical system, including the engine alternator mounting bracket and the installation of a Balmar MC-618 External Regulator with the intent of installing LiFePo4 Lithium Batteries in place of the current Lead Acid House Batteries. The LiFePo4 batteries can pull a substantially higher charging current than the LA batteries. So having a drive belt system that can drive the engine Alternator is important.
Several of my buddy sailors have upgraded their engines (not necessarily the same engine we have,) with a serpentine belt system. They have been very impressed with the results.
Looking up the details of the Serpentine kits online, I found that one important issue was that the replacement engine pulleys are wider than the existing pulleys by about 1/2". I checked our engine and confirmed there was at least 3/4" space between the front face of the existing pulleys and the engine sound insulation that is on the back of the cabin steps that form the front cover of the engine space.
I ordered the Balmar 48-USP-M25 Serpentine belt kit from PKYS.com - it has come down in price over the past few months and only cost $472.94 total including tax.
In the online order, I asked if they would confirm that it was the correct version for the Universal M25-XP, their response was that I should confirm the version myself.
A member of the C34 Association suggested that I contact Balmar directly. I did and Mike from Balmar confirmed that I had the correct kit version for our engine. I then contacted PKYS.com and confirmed the order.
Rod Collins from marinehowto.com advised that I should ensure that the crank pulley on the engine is a 3 hole fitting to match the kit. It does ( but I had to go check )
Here's the kit:
I confirmed that the Coolant Pump Pulley is replaced by the new one ( the pulley on the left of the picture.
The Crankshaft pulley fits over the existing crankshaft pulley.
Note there are two of the serpentine belts, one is a spare.
Of course, some of the kit components are out of stock.
Here's the plan.
Remove the engine cover ( cabin steps ) and remove the existing V-Belt.
Try to remove the Alternator Pulley - If I cannot get it off then remove the Alternator and take it to a local shop and have them replace the pulley.
The new Crankshaft pulley fits over the existing pulley, I have already confirmed that the bolts are not seized, so install that pulley.
The same goes for the Coolant pump Pulley.
Install the new Serpentine belt and adjust the belt tension by adjusting the Alternator support arm ( note that I'm using a modified support arm that I had made locally )
Test it, run the engine over the full RPM range, Check for belt slippage ( squeal )
Recheck Belt tension.
All done.
RIGHT! Boat projects never go that easy!
Our plan ( Peggy will be helping offering moral support ) is to go down to the boat when the kit arrives and get down to it. We're taking the boat out for our sailing club's annual Circle Raft up on March 3rd. -- No pressure --
2023.02.24 09:00 - Just received notice from PKYS tracking that the package should arrive today before 9pm although it's 'out for delivery' right now.
Our schedule is Busy Saturday, We don't go to the boat at the dock on Sundays, but I should be able to start the install on Monday Feb 27th. It's going to be tough but I was planning an article for the Catalina Mainsheet magazine about the install, that would be due delivery by March 1st. - NO PRESSURE -
1st attempt to install the new pulleys.
I was able to remove the outer pulley on the Crank Shaft ( the existing pulleys are all twin belt pulleys ). Basically I removed the three bolts that secure the pulleys to the crank shaft and remove the keyway hex bolt then use a 3 Jaw puller to remove the outer pulley and expose the original inner pulley.
The new Balmar Crank Shaft pulley is mounted over the existing inner pulley, but it does not fit.
The Original Inner Pulley is 130mm diameter
The new pulley's internal diameter is 127mm
( That's measured with my plastic Dial Caliper, so not likely to be that accurate)
And I confirmed that I cannot remove the pulley from the alternator, so I will have to remove the alternator and take it to the local shop and have them remove the old and install the new. But first I'll have to figure out the issue with the Crankshaft pulley. There's a local Kabota dealer just 10mins from my house and they are always helpful, but I'll also contact Balmar to see if they have a pulley that will fit over our crankshaft pulley.
I put everything back together and ran the engine for 10 mins to make sure all was well. We're taking the boat for a weekend trip starting Thursday (tomorrow) evening. We're good to go.
The task continues.
I finished work early the other day ( Thursday) and went to the boat to see if I could pull the Engine Crankshaft Pulley using the same puller as in the pic above. There's a heavy duty tab washer keeping the Nut on the shaft, I was able to bend that back out of the way and then used a Socket and wrench to remove the nut. It took a few whacks of a hammer to loosen the nut but it came off after a few minutes of effort, then the puller easily removed the pulley and the 'key' fell out as I removed the pulley from the shaft. I was pleasantly surprised how easy it was to get that off.
Next item to tackle was the Alternator pulley. I didn't think I would have any chance to remove it although I did have a suitable socket. The alternator spins so easily I didn't think it was worth trying. So I disconnected the main battery +ve at the battery and then I removed the Alternator putting a piece of Heat Shrink tubing over the bare end of the big +ve wire so that I could reconnect the battery in order to keep power available to the Bilge Pump.
With the Crankshaft pulley and the Alternator in hand, I headed to Fort Lauderdale to visit the machine shop and battery / alternator shop. 1st stop was Fort Lauderdale Battery & Electric. They have been really helpful in the past and I think that the majority of patrons go there with a 'problem' whereas I've been fortunate enough to know what was needed and they always come through. I showed them the Alternator and the new pulley. Two minutes later it was all done. Barely had time to warm the seat at the counter. ( Here's a link to the last time I visited them ) Within 10 minutes of arriving I was leaving the shop with the alternator wearing it's shiney new Balmar Pulley.
Next stop was Tropical Marine just down the road from the Lauderdale Battery & Electric shop. They had made the modified Alternator Support Arm ( here's a link to that article ). They are going to turn the Engine Crankshaft Pulley down so that the new Balmar Pulley will fit over itl, an easy fit. Should be ready this week.
So! Making progress.
Important note. A boating buddy also installed the Balmar Serpentine belt kit on his Boat's Generator. Within just a few hours, the belt was damaged due to misalignment, so I'll be careful to measure the alignment when I put this back together. Probably make a separate post about that, but I think that I should be able to shim any of the pulleys outwards in order to ensure alignment.
Waiting on the phone call from Tropical Marine.
Tuesday, March 16th. Got the call from Tropical Marine, it's ready for pickup.
Wednesday: I drove down to Tropical marine before heading into work today, the new Pulley now fits around the Crankshaft Pulley, it's ready to go. Oh, and all of the holes line up.
I'll work on Monday and Tuesday and take off Wednesday to complete the Serpentine Belt upgrade for the engine. We must not run the engine yet as our Prop shaft has a problem that the divers should fix in the next few days.
Wednesday March 22nd.
Well, that was not a real surprise! The belt is too long!
Down at the boat this morning, I cleaned up the front of the engine with some Spray 9 and a bunch of rags, it looks Spiffy.
Next I installed the Crankshaft Pulley, remembering to apply the TefGel onto the face of the new pulley that touches the old Crankshaft pulley. I did not apply the Loctite to the pulley bolts as I wanted to check the alignment first.
Next was the install of the Coolant pump pulley, that went without a hitch.
Finally install the Alternator that now wears a nice blue Balmar Pulley on the front spindle.
Next was to install the new Serpentine Belt over the three pulleys, and there's the problem. The new belt is at least 1cm too long. The alternator would be sticking out of the access door in the bathroom.
Grrrr. But what the heck, it's a Boat!
I called Balmar and the belt is 42" long and they have a 41" belt. They cost $74 each plus shipping.
After picking my jaw up from the floor, it was explained how they would exchange the 42" belts for the 41" belts if I mailed them to their facility in Alabama.
So that's the plan.
Oh, there's another issue. The belt tensioner that I made to use on the V-grooved Pulleys that I have now removed, does not play nicely with the new Aluminum Pulleys. I'll have to polish out the scratches on the surface of both the Crankshaft Pulley and the Alternator Pulley. At least that's easy as they are Aluminum.
Ok, held up for a few days. I'll mail the belts tomorrow.
Stay tuned.
Change of plans!
My buddy has replaced the V-Belt on his boat's Generator and had the same issue, belts too long. He suggested I contact VBeltGuys.com. I did, Two new 41" belts arrived 3 days later and cost less than the shipping both ways to balmar. So I'm not sending the balmar belts back - if you know anyone that wants a pair of 42" 10 ridge Serpentine belts free for pickup or shipping --- let me know.
Thursday March 30th.
Went down the to boat, completed the install of the belt and checked the alignment, looks as close to perfect as I think I can get it. Ran the engine, all worked pefectly, the belt did seem to stretch/loosen a little, but I retensioned it in about 5 mins.
Oh! Forgot to mention: When I used my home made belt tensioner to try and tighten the 42" belts ( unsuccessfully ) the tensioner damaged the alternator pulley surface. Today I took a set of fine files and removed any burrs off of the alternator pulley. Note: Do not use a tensioner that might damage the pulleys!
Once the tension was correct and aligned, I removed the bolts for the Crankshaft pulley, one at a time and applied the Locktite supplied with Balmar Serpentine belt kit. Then did the same for the coolant pump pulley bolts. The final thing to do was bend the tabs of all of the locking washers on the alternator support arms and re-run the engine to confirm all was good - it was.
Phew, so glad to complete this project. Of course, the engine sounds a whole lot better or is that just that my ears are satisfied with completing the project.
Here's all of the info about the kit, PKYS and Balmar, Lauderdale Battery & Electric and Tropic Marine products.
Kit:
Balmar 48-USP-M25
Cost:Subtotal: $442.00Discount: $0.00Shipping: $0.00Sales Tax: $30.94Total: $472.94
Purchased from PKYS Inc.
7416 EDGEWOOD RD STE 3ANNAPOLIS MD 21403410 280-2267
Balmar:
15201 39th Ave NE
Marysville, WA 98271
Customer Service: 1.360.435.6100 x1
Technical Service: 1.360.435.6100 x3
Fort Lauderdale Battery & Electric
2415 SW 3rd Ave, Fort Lauderdale, FL 33315
Tropical Marine
Tropic Marine Products217 SW 29th StreetFort Lauderdale FL 333015Phone: 954-779-7038
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