1975 volvo AQ225A cracked exhaust riser

[jerryjerry05]

Re: 1975 volvo AQ225A cracked exhaust riser

Send a pic of the pump and the impeller along side a ruler to cobe.

 

[captmello]

Re: 1975 volvo AQ225A cracked exhaust riser

this sure looks like your pump...

Sea Water Pump: 835463 : 835463 - 7740880 - Volvo Penta

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

I took measurements of impeller and found one at NAPA. Should have it today. Getting closer each time. I just hope this is it. I really don't want to dismantle the exhaust system.

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

Installed new impeller. It is pushing a lot more water now. With old impeller the hose running to the engine water pump never had much pressure i.e. the squeeze test, its firm now. lots more water out the exhaust. I even have water running out the over flow tube on the out drive.(that's what the hose in the back of the risers is for) Temp. gauge is still reading 200. I am going to install a mechanical gauge next. I am not trusting the old electrical unit. Is it possible to back flush the cooling system? Or do I have to dismantle and clean each piece separate?

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

Ok, I pulled the starboard exhaust. I do not see any blockage. But, I do see a lot of iron flaking off. Before i pulled the exhaust i did run the engine too see if it was getting hot. I didn't trust the elect. temp gauge. so I checked by placing my human flesh on the manifold and riser... Ouch ! it was very hot. If I understand correctly it should be warm to slightly hot to the touch. that's why i pulled the exhaust. I did ask COBE marine for info as to what all they have for my set up.

 

[captmello]

Re: 1975 volvo AQ225A cracked exhaust riser

What did you pull? the riser? The exhaust will get hot, especially if your running on muffs. One may get hotter than the other, that's normal. Still waiting for a usefull temp gauge, even an IR thermometer can be useful, got one?

If the flow is being slowed by corrosion, there's not much you can do. Im not saying yours is clogged, but you can't clean them out, backflush.
If there is a plug in the bottom of the mani, at the back you could try pulling that and seeing if its clear. My manifolds had a bunch of sand in it from swallow water boating...

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

I pulled the riser and manifold on the starboard. What is IR thermo? There is a lot of metal flaking off inside the riser. Walls are looking thin. I really don't like guessing on a problem. But, I also don't want to drop money where its not helping either.
Thanks.

 

[captmello]

Re: 1975 volvo AQ225A cracked exhaust riser

Can you post a picture of the mating surfaces between the riser and manifold? clean the surfaces good, so we can get a good look. Pics, pics!

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

sorry, no pics yet....
after contacting cobe marine and a local Volvo dealer. I have decide to figure it out myself. I don't want to offend any one but I am getting tired of "professional marine mechanics" telling me that I don't know what I am talking about and that my motor set up doesn't exist. I have spent most of my life rebuilding old cars. So, I am familiar with shops trying to tell me that something doesn't exist. But, I am getting tired of it. I have been forced to become a engineer and a mechanic only because people are becoming lazy. Even Volvo will not confirm if the " Chris craft" exhaust is the same as the 1973-1975 Volvo penta AQ225A exhaust set up. I actually had the local marina try to argue with me that my set up was not original. I told them to go to the volvo north america site. then they came back and said oh, cant get that part. They still don't come up with a solution. Just, oh well... Sorry for the rant! I thought rebuilding cars was a challenge... Boats are a whole nother world... I have JB welded the starboard riser. It turns out that both the starboard and port side over flow valve were packed full of debri. I.e. rocks and pieces of impeller. I am now cleaning all mating surfaces and getting ready to re-install.

 

[captmello]

Re: 1975 volvo AQ225A cracked exhaust riser

Boats and cars are so different. There isn't the aftermarket parts available for the older stuff, especially unique models like yours. Finding mechanics who know how to work on them can also be difficult. But it sounds as if you are up to the challenge. Have you gone over the outdrive at all? If you think the motor is unique, wait until you start working on the outdrive! :facepalm:

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

You got that right! I don't mind working on the old and unique. I currently have a 57 Cadillac, a 60 ford F250, and a 86 FJ60 landcruiser. All of which I have done most of the rebuilding. I just don't like having to argue with people. I'm not a cant kind of person. As for the outdrive its a 280 volvo penta. I have only checked the fluid and the condition of the bellows. I can already see that I will have to change the fluids. Previous owner put 90 weight gear lube in. Volvo calls for the same motor oil as used in the engine 10W 30. Well, one step at a time. Hopefully i will get the time this week to put the exhaust back together.

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

OK, so now i am getting ready to re-assemble the starboard exhaust. Since i am having so much trouble with getting Volvo or any shop to confirm whether or not the AQ225A exhaust and the Chris craft exhaust is the same. I am thinking of just using gasket maker like ultra black or right stuff. Any ideas or suggestions? I have used both extensively on automotive. I am uncertain if they will work for sealing between the exhaust and water jackets in the exhaust.
Thanks

 

[captmello]

Re: 1975 volvo AQ225A cracked exhaust riser

Is the gasket for the CC manifold to riser available? If so, just buy it. There aren't that many different manifolds out there. back in the early 70's as the I/O's gained popularity some of the boat manufactures began Marinizing there own engines. Chris craft, was one, and Glastron was another we see here on the Volvo forums a lot. Glastron used Volvo outdrives, but bought manifolds and other marine specific parts from different manufacturers. Anyway, Non of them did this for very long. I doubt Chris Craft was actually manufacturing their own manifolds. the fact that you can still buy both the manifold (Cobe had them on their site), and riser, suprises me actually. but someone is still making them.
Like I mentioned before. You do not want the manifolds to leak water back down the exhaust.
I like your stick-to-it attitude, and I hope you can get some use out of this boat after all this.
As far as form-a-gasket type products...I think I would just use some of the sheet material they sell at auto parts stores and cut my own.

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

I took your advice Captmello. I ordered the gaskets for a chris craft log style exhaust set up. They are the same, all the gaskets matched and the exhaust is working perfectly. engine temp. is now holding at 160. Now I know that the Chris craft log exhaust and the 1973-1975 Volvo exhaust is the same. Next season I will order new risers. Now on to the out-drive I will change fluids tomorrow. I have read in the original owners manual(downloaded from Volvo) that it will use the same engine oil as the engine 10W-30. I also read from another source that the newer outdrives use ATF and that I should use that . What do you think? I am thinking of staying with 10W-30.
Thanks for all the help.

 

[captmello]

Re: 1975 volvo AQ225A cracked exhaust riser

great to hear you've got is back together and up and running. Yes, engine oil is what you want in the outdrive.

Good luck!!!!!

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

After getting it all put back together. Exhaust risers, impeller, t-stat, and electrical issues. Its time to do a test run on the lake. Heading out tomorrow morning for a quick run to make sure all the bugs are worked out. Very excited to see this 38 year old boat go.

 

[captmello]

Re: 1975 volvo AQ225A cracked exhaust riser

That's one of the coolest boats I've ever seen.

Good Luck!

 

[dozer59044]

Re: 1975 volvo AQ225A cracked exhaust riser

Thanks.
Well, she runs great. Every thing is working properly. Boat planes out nice. Runs very strong. Even stopped to have lunch in the galley.
Awesome fun with the family. thanks for all the help and advice. We got a lot of looks from other boaters. You don't see boats like this often.
Thanks