Looking at refreshing a clean and tidy 1984 Suzuki DT85. It's done around 350 hours, has good compression on all three cylinders, starts easily, idles smoothly and generally runs well. Last time I had it out it topped out under 5000rpm though where it used to hit 5500rpm+, likely due to fouled carbs - it sat for two years without being run.
My planned hit list is:
- decarb cylinders (Seafoam or similar)
- ultrasonic carb clean, carb kits, floats, fuel/air adjust, idle adjust, carb synch
- new engine filters throughout (fuel; oil; various gear case water filters)
- new coil packs w/ integrated leads, spark plug boots, plugs
- new fuel pump assembly complete
- new oil pump assembly complete
- new reed valve assemblies complete
- new thermostat, gasket, housing
- new anodes
- new gear case oil
- new tilt and trim fluid
- water pump kit (impeller, key, face plate, gasket)
- grease all nipples + steering/tilt rams
- gasket set for all removed/replaced parts
It's around $750 for the bits to do the above and I'll do the work myself. Any thoughts as to items I've missed but should address would be appreciated. Some items like the coil packs are probably overkill, but they're available at the moment (not guaranteed in a few years time) and not overly expensive so eh. I'll keep the old bits as emergency spares.
Also planning on replacing the original steel totes with new poly totes and fuel line including an inline filter (maybe fuel/water separator too; not sure it's needed with totes though).
Not sure whether to replace the thermostat with the factory standard 42°C or the factory optional 62°C. What conditions justify the higher temp rating?
It's an old 2 stroke, some of the stuff you mention is not applicable, not too sure why you would replace working coils or reed valves, I would give the Seafoam a miss too, water pump kit (genuine) gear oil, plugs, carb cleaned properly, thermostats and see how it goes, broken bolts are going to be a drama I would think.
Reed valves can crack, they're 35 years old and it's $60 to replace all three, so I figure I may as well while the carbs are off. Likewise the coils and leads are fine now but they're ancient, so at $120 for the three it's a potential issue fixed before it occurs.
Seized bolts shouldn't be much of an issue. I had the lower unit + carbs off a few years ago to replace the impeller and clean out fouling and nothing was seized up. Might be different on the exhaust side of the block.
It's a gifted boat owned from new by my father. I'm picking it up in a few months time (interstate) but looking at placing a parts order now so I can have it ready for summer.
I have a ultrasonic cleaner i doubt it will clean varnish from a carby that has sat dry for 2 years what i do with my tank i fill it with hot water so its already boosted up near operating temps than pour degreaser into the water than get a can of carby cleaner and spray the carb cleaner directly into the water put the lid on and keep cycling it and let it sit in the hot water for a few hours give it another clean after soaking for a few hours
Carbies should come cut clean but if u still have varnish stains u may need to soda blast inside the bowls
Soda blasting marvalous tool i have a gun and just use regular woolworths 500g bags of baking soda i recently done a whole dirt bike engine came up like brand new
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Yeah, you generally need to use a cleaning fluid for ultrasonic carb cleaning. Water alone won't do it. Soda blasting isn't a bad idea though, thanks.
Yep, reeds can crack, probably one in about 10,000,000 ever fail, but, it's your motor and your cash, replace what you like.
sounds like the go refurbish the suzie ....are ya just gonna go ebay for the coil packs aftermarket or try to source genuine ones , share with us if you find a good seller for coil packs cheers
Have heard of some of the old Zuk's cracking the gearbox housings due to corrosion. First thing I would do before dropping any amount of money is pull the prop and the gearbox and have a very good look for any cracks or corrosion - up in the leg as well.
Probably a great call there Scott. Weren’t these models that ones that got the Asprin nick name?
Democracy: Simply a system that allows the 51% to steal from the other 49%.
Now I'd forgotten (from a previous thread) that my DT85 did suffer a crack, it would certainly be worthwhile removing the gearbox and giving it a good clean. There was no corrosion in the water galleries as they were of a decent size and you needed something the size of a math head to block them.Originally Posted by scottar
Thanks, good advice there. I don't remember any sign of corrosion when I last changed the impeller, and I bled a little gear oil last time I took it out and it wasn't milky, so I'd say it's okay. I'll check it out closely though.
Unfortunately they weren't known for their metallurgy. A good mate had a DT200 that cracked the gearbox. Apart from that it was a good engine. The corrosion may not be seen in where the water pump is. From memory it was down in the lower area that houses the gears. I would be pulling the prop and if you have access to an inspection camera, take a good look up through the hub. Also check up the exhaust and have a good look at the adapter plate that sits between the power head and the leg using a torch
Also check the trim and tilt ram assembly for corrosion and hydraulic leaks and full operation
I had a 30hp of that era ran like a dream on the muffs... but it had a huge corroded hole inside the exhaust
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