First let me say thank you to all members here. Been a lurker for a while and learned some great stuff. Unfortunatly, this time, I'm stuck. I have a '89 force 125 on a 89 bayliner capri. We were out last weekend running along fine, then she bogged down and died and would not restart. Fast foward, I believe she over heated and the buzzer was inop. I changed the impellor and thermostat with help from reading on this forum. My problem now is that I can not tell if it is working correctly. I had ear muffs on and set the motor in a large bucket of water. I ran her for a while and could not tell if it was pumping water so I pulled the thermostat off and found the inside to be bone dry. I am wondering if there is a clog some where or is this normal. The motor starts up one the first try but runs ruff and after a while dies out. Can I run some sea foam in the fuel and use carb cleaner at the same time.
It's often very difficult to get proper water flow with the muffs. Also if you're using a bucket, it has to be large enough to submerge the whole lower end up to the cavitation plate to work properly. If you're sure you have the muffs on and aligned properly, and the lower end is submerged low enough and still no water, then I would suspect that you have some type of blockage. Either a piece of the old impeller (was the old impeller intact, or were any of the fins missing?) or you may have sucked up some mud or debris clogging up the water passage. You can try and back flushing the water passage from the thermostat opening with your garden hose. When you stick the end of the hose in the opening, use some rags to get a good seal to maximize the water pressure to force the gunk out. I would suggest that you take the lower unit off when doing this so that you don't push any debris into the water pump. Put a bucket under the motor when doing this so you can catch and see any stuff that may come out of the block.
Second thing that you may want to check is compression. Verify that no damage to the block or head gasket if you suspect it has overheated.
Thanks pnwboat for the suggestion. I am wondering about a blockage myself. The bucket I was useing is large enough and I am pretty sure the muffs were placed correctly. I am just confused why I don't have any water flow. As far as running ruff, I was thinking that when I ran it in the river, I may have had some bad gas in it. That is why I was wondering about running some sea foam in it to help de-gum everything.
If you suspect bad gas, obviously the best thing would be to drain it out which can be a problem. You may be able to siphon it out. If not, then you have no choice but to try and add some Seafoam, Drygas or something similar depending on what kind of contamination you have. What ever you do, don't spray pure carburetor cleaner into the motor while it's running. There's no lubricant in the carb cleaner and you'll wash away any existing oil which can result in damage to the bearings and or pistons/rings/cylinder walls.
Boy I am sure glad I checked back here. I went just a little while ago and picked up some sea foam and carb cleaner. I do appriciate your help with this. I droped the lower unit today and back flowed the system. I did have some parts of the old impeller in there, just not a 100% sure it was clogging it up. I did however notice it did run better (with muffs) than it did last time. I am going to try and get to do the compression test this week. I don't believe that any damage occured to the head, but you never know. The only bad news I got is that I got to wait untill next weekend to put her in the water to see what happens.
It doesn't take much blockage to disrupt the flow of water. Sounds like you probably are OK now. Compression check is just a precaution. I always do a compression check at the beginning and the end of each boating season to keep tabs on the shape of the rings and cylinders.
Buy the loudest buzzer you can from Radio Shack. They must have 20 different buzzers that will work at 12 volts. To check your buzzer, remove the orange wire from the thermoswitch and ground it. If the wiring and the buzzer are good, it will set off the buzzer. If you have a black colored thermoswitch, I suspect it may not be working as they were superceded by red ones.
You can buy a temp gage from West Marine for about $35 bucks. It comes with all the parts needed to install.