how to replace thermostates 1990 115hp?

[reeldutch]

how to replace thermostates 1990 115hp?

I have a 1990 115 evinrude and i would like to change the thermostates.<br />Normaly to change the thermostates i have to lift the powerhead to reach the thermostates.<br />a mechanic will charge me $400 to do this job.<br />just to put new thermostates in is absurd.<br />is there a other way??

 

[DHPMARINE]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

Reeldutch,<br /> If your themostat housing is mounted low between the cylinder heads,this may not be too bad an estimate.The job can been done with out pulling the power head.Just a guess parts to be about $75.00.That leaves $325.Now look where the 3 bolts on the housing are.Now add corrosion,and add it twice more for salt water.Now divide by the shop rate,and $400.00 goes way too quick.If I had this engine,thermostats would be done every year.(and if one of the three bolts break....?)<br /> I have seen suggestions to drill access holes in the lower motor cover,but never seen it done.Maybe a good idea.<br />DHP

 

[ledgefinder]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

If they're real clean, I sometimes can get the three bolts with a real well-made, good-fitting (i.e., Snap-On brand) 7/16 box wrench. I try that first. Heat can't be used, because one of the housings is plastic (right?). If the motor's real clean, or if the bolts have been out recently, it'll work. Otherwise, off comes the powerhead, & I do the carbs & water pump at the same time.<br /><br />Too bad it's a tough job, because those dual thermostat systems fail open a lot in the salt (in my limited experience), and are something that really needs to be serviced.

 

[reeldutch]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

if i would drill accesholes trough the lower cover to get the bolds out is there enough space to get the thermostates out and put new gasket on etc..<br />And how would i coverup the 3 holes to prevent water from comming in. (rubber?)<br />Yes i agree i should do this every season because i fish in salt water.<br />I always flush with freshwater but that garantees not much.<br />If somebody had done this i would like to now if it is a good way to change the thermostates.<br />thanks.

 

[DJ]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

You can remove the bolts that hold up the lower cowl pan. That will allow you about an inch or two of access. You first must remove the bolts holding on the clamshell cover just below the lower pan.<br /><br />It can be done, just be patient.

 

[rodbolt]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

hello<br /> if ya break one off the poer head comes off. not a lot of fun but doable. I have a friend thats a welder and he cut holes in his with a hole saw and I drilled them out and he welded the slugs back in place. but thats beyond most resonable repairs. if the bolts are stuck you can remove the latches and coils for extra clearence. then I either use oxy acetylene to melth the housing or an air chisel to crack it, just depends on the motor. usually the bolt is stuck in the housing not in the power head adapter. patience is the key here. and quality 6 point tools. the housings are less than 30 dollars or so new sodont be afraid to destroy them if nessasary.<br />good luckand keep posting

 

[OBJ]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

And when you get to the point of putting it all back together again, before you put the housing bolts back in, give them a good coat of gasket sealing compound. This will stave off the effects of salt water and let the bolts come out easier next time.

 

[J. Fenn]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

I have to do this job as well on my '84 1.6L Seadrives. On the stbd. engine, the bolt heads are so corroded that there is really nothing left to grab with a wrench or socket head. I need to study it some more, but tentatively my plan is to slip some blocks of wood below the housing and cut off the bolt heads with a cold chisel. After I pull off the housing, I'll work on the bolt shafts with a vise grip and some PB Blaster. I'll replace the bolts with stainless and coat the threads with sealant before reinstalling.<br /><br />I've seen a few recommendations for flushing with Salt-away after running in salt water. I plan to give it a try after I get my cooling system mtnc. work done.

 

[Jack Shellac]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

This is a too frequent job on my 1990 saltwater V-4, so I drilled two holes in the lower housing directly behind the bolts. Just big enough to put a 1/4" drive extension through. Put the socket on after the extension is through the hole. This makes it easy to get the bolts off, remove the housing and service the thermostats and pressure valves. Snap-in rubber grommets cover the holes afterwards. OMC gasket compound will help hold the gasket in place when you're trying to juggle the assembly back in to bolt it down.

 

[reeldutch]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

thank everybody,<br /><br />so jack you dont have eny problems getting water<br />trough the holes? Rubber works fine?<br />because i am thinking about drilling the holes<br />and service the thermostates myself every year.<br />do you eyeball when you drill the holes ore do you mesure?<br />i cant believe i am gonna drill these holes, i hate doing it bud it seems the cheapest way to service the terms. <br />Oh yeah shouldnt i have to drill 3 holes.<br />I have 3 bolds in the thermostat housing.<br /><br />reeldutch

 

[Solittle]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

Make sure that the rubber grommets are well sealed. Water injested in these motors is fatal and is very expensive - I know the painful way.

 

[reeldutch]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

i did drill the holes and it was easy to acces the bolts. They came out fine. I can clearly see that there is some salt buildup. not as bad as i tought it would be. do i have to pull the cillinderhead covers to clean out there or just replace the therms an waterpump.<br />I did not have a overheating problem just want to be ahead.<br />i do think that even tough the engine is rebuild<br />the cillinderheadcovers have never bin pulled of.<br /><br />thanks

 

[Jack Shellac]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

If you're using it in saltwater, run some Salt-a-Way through it on a regular basis. I just tore down a 15 HP that was saltwater corroded and soaked the parts in this stuff and it works. The deposits softened up and came right out.

 

[Solittle]

Re: how to replace thermostates 1990 115hp?

Re: how to replace thermostates 1990 115hp?

Leave the heads on but follow Jacks advice. Also do the water pump.