1985 evinrude 30hp overheating

[pinky_IM]

ok, lets start with the classic and timeless tell tale background, i was fishing too close to the weed bed, something got stuck in the impeller, overheated and smoke poured from engine, this was last year. i started to try and fix it about a month ago, replaced water pump with kit, no problems, water came out the pee hole ok but not in a full stream, took head off/exhaust cover off and removed a LOT of plastic from the old water pump that melted and got into the water and engine. cleared all plastic and removed the thermostat. engine runs and pisses like a champ but after running it for a while, the buzzer will go off (overheats). i have checked everything i can think of, 3 times over...removed and reseated the water pump multiple times, the exhaust and cylinder head multiple times and still am unable to determine why it is overheating...water is flowing and good, please help??

[OBJ]

Welcome pinky!If your running without the t-stat and it's still overheating, chances are that some of the old impeller have got stuck in the water tube from the pump. Probably where the tube meets the block. There's a water tube adaptor and grommet there. The grommet might be deformed from the heat and blocking full water flow also.

[pinky_IM]

sorry, forgot to mention specifically, when i replaced the water pump, i also verified nothing was stuck in the water tube, the driveshaft housing was replaced (the tube from the water pump to the upper part of the lower unit covering the driveshaft). the water tube itself was clear from any debris, tested water pump using drill with correct socket (so as to not damage the teeth) with water tube connected and the whole lower unit submerged, water came up tube fine, not to mention that i said that the water was pumping out very good (healthy stream). i need some more testing to the engine to test water flow, is there anything that i can do to test the water flow within the engine itself? i can see all the way up where the water tube connects at the lower part of the engine block and it is clear and free from debris. you mention there is a water tube adapter (can you explain a little further or point me to a link that shows a picture) and any information about the grommet would be good too as i have a SELOC book but it doesn't show either? is it hard to replace? what needs to be removed to get to where the tube meets the block?

[Walker]

Does you Seloc show water deflectors in the engine blosk under the heads. Perhaps you removed them when you cleaned the "plastic" from the motor.

[pinky_IM]

if there was anything in the water jackets around the heads, it has been removed...i didn't see any real parts, just a hunk of plastic... and no the seloc book doesn't show water deflectors, if you could point me to a link/picture it would be helpful... i will research myself and see if that helps.

[Walker]

They are short pices of rubber hose about 1" long stuck in the water jackets of the cylinder. 2 per cylinder. Pull a head and look in the block around the cylinder.

[OBJ]

Two deflectors in that head. Without them or if there damaged, the engine will overheat.

[pinky_IM]

definitely no 'water deflectors' or rubber anything, as i am sure it melted as well and all pieces of rubber were removed from water jackets...so that sounds like my problem...i will post when i get new ones and install them.

[pinky_IM]

ok, what i got from a dealer was a 5" long 1/4" thick circular solid flexible rubber hose, so then i called around and found out that there is suppose to be one piece 1-2" long in the top of the upper cylinder and two pieces (same size) in the bottom and i looked closely in the water jacket and can see little divits/protrusions where these are suppose to be so i cut the 5" piece into 3 pieces about the same size 1-2" and installed them in the respective locations in the water jacket, and put in a new thermostat as well, and still no go, it is still overheating after all this and water is pissing out the pee hole still really good and it gets warm but not hot. so my problem still exists but not sure where to start next or if i did install the water deflectors correctly...i can take pictures of the install if it helps but i have a feeling the water deflectors helped but its still overheating but pumping water like a champ.

[pinky_IM]

just a follow up. after replacing the water pump, water deflectors and using it for some time, it continued to overheat, so i brought it in to the shop, paid $160 and the guy told me the water pump was fine and gave me a little grommet that goes into the bottom of the upper unit. I had to remove the whole engine from the housing (about 12 bolts) and a couple were very difficult to remove, pulled the engine up and there is an exhaust housing that the water pipe plugs into and the grommet was for the top of the water pipe. there was nothing there, had to dig out the hole in which it went into and figure out how to put it in (it goes in from the bottom) but you have to remove the engine from the housing to do the work. so he told me where it goes and said it would cost me a lot for him to do the work, so i did it myself with little to no trouble and it took approx. 6hrs (for a rookie) (think i may have bent the idle screw a little when i pulled the engine out) as i laid it on the front to put the grommet in. hopefully this assists someone.


one last note, when you replace an impeller, make sure you put a little grease in the impeller area so it moves smoothly, but not too much as you may plug a hole (the holes are tiny).

[pinky_IM]

Welcome pinky!If your running without the t-stat and it's still overheating, chances are that some of the old impeller have got stuck in the water tube from the pump. Probably where the tube meets the block. There's a water tube adaptor and grommet there. The grommet might be deformed from the heat and blocking full water flow also.

this is the grommet i received (ty), didn't think it was a problem as i connected a hose to the water pipe/tube and water came out the pee hole but i shouldn't have taken your advise for granted as the grommet is absolutely required and makes a big difference.