getting at thermostat bolts EV 90 '85 flat

[mutron77]

Hello,<br />I thought it looked easy to get at the thermostats, now I see the dilemma, the two lower bolts are too long to clear lower engine cover. Why not have put in access holes with rubber plugs on the back of the lower cover? Now I am looking at the tray bolts and power head bolts and scratching my head about how to lift the head to get them out and imagining all manner of things popping loose. I am about to go get my drill like 'reeldutch' and pop some holes in there big enough to get a socket through.<br />Someone please share the correct way before I start hackin'.<br /><br />H90

 

[DJ]

Re: getting at thermostat bolts EV 90 '85 flat

Horse,<br /><br />It can be done.<br /><br />You will have to take the lower pan bolts loose and remove the midsection band just below the engine pan.<br /><br />You will also have to remove the air silencer.<br /><br />Once that is done, you can pull the rear of the pan down far enough to gain access to the bolts.<br /><br />Done it many times. Yes, it's a pain.

 

[mutron77]

Re: getting at thermostat bolts EV 90 '85 flat

Ah, a ray of hope...<br />Some terms I need to clear up, Is the "air silencer"<br />the manifold type thing that bolts to the front of the carbs? And please, can you describe in more detail what this midsection band is and, what it looks like, and how many lower pan bolts there are?<br /><br />Thanks,<br />H90

 

[OBJ]

Re: getting at thermostat bolts EV 90 '85 flat

Yep, the air silencer is the thingy bolted to the front of the carbs.<br /><br />The ring DJ refers to is just below the lower engine pan. You will see two 5/16" bolt heads toward the front. Remove these. Look inside the pan below each head and you will see a 7/16" bolt head. Remove these. The large portion of the pan should slide off toward the rear. If you need to remove the front half of the ring, there are two more 5/16" bolts to remove. These are around where you took the first two out and are inside.

 

[mutron77]

Re: getting at thermostat bolts EV 90 '85 flat

I'm not quite getting it. The lower engine cover seems to be one solid piece, not two halves. there are two 7/16 bolts below each head. One seems to be the head mount and there are two more in the pan itself. There seems to be several other points where some bolt or other bolts to the pan I can see two underneath on either side towards the front.<br />confused!!!!<br /><br />h90

 

[reeldutch]

Re: getting at thermostat bolts EV 90 '85 flat

the reason why i drilled the holes is because i want to change the tstat every year.<br />after i replaced them i run the motor and found out one bank was cooler than the other. <br />i took the bolds out again and tried it again.<br />after i run the engene and everything is fine i bought some metal epoxy and a can of spraypaint<br />and you realy have to look good to see there where holes.<br />now i know how to do it and i will let you know<br />how everything works out after a few weeks running in salt water.<br /><br />good luck , reeldutch

 

[DJ]

Re: getting at thermostat bolts EV 90 '85 flat

Horse90.<br /><br />The "band" I speak of is the cover that covers up the top of the exhaust housing. It does look like one piece. That is because the bolts are in front of it-just behind the clamp bracket.

 

[mutron77]

Re: getting at thermostat bolts EV 90 '85 flat

Thanks guys. I'll tkae another look. I think I will have to get the OMC manual. I am about to order one anyway. I guess I need pictures to clear this up. I all looks like a maze to me under there.<br /><br />H90

 

[Solittle]

Re: getting at thermostat bolts EV 90 '85 flat

H90 - Also order the parts catalog to go along with the shop manual. They have great parts explosion diagrams.<br /><br />I did the t-stats on my two 1987 1.6L SeaDrives last year. They can be done without pulling the powerhead or drilling holes. I did drop the pan as others have mentioned. I loosened the two lower bolts from below using a 7/16" box wrench. Once they were started I used a 1/4" drive socket with a very long extension and universal joint from the top of the pan. When ready to go back in I used rubber bands to hold the assembly together until the bolts got started - then cut the rubber bands.<br /><br />When you put the hoses back on the cover make sure that you use tie wraps for hoses - they are a little bit different than the electrical ones and will assure a better seal - use them also for any other hoses that carry water under pressure anywhere on the motor - - the reason I mention this is I had a small hose let go back there last year at 4500 rpm resulting in a little salt water firehose which resulted in a rebuilt powerhead.