1989 Stingray 5.0 Ford OMC engine froze

[race24x]

Hi there and thank you for letting me join. I was an auto mechanic for many years and have worked on several boats with I/O drives. I have a 1989 Ford OMC this time with the 5.0 Ford 2 bbl carb with only 55 hours on it and it appears they tried to winterize it and didnt do a very good job. I cant see a crack in the block but 3 freeze plugs need to be replaced. The manifolds are cracked and leaked water into the cylinders. I removed the manifolds and spark plugs and used the starter to pump the water out. I then left the manifolds off and started the motor. It seems to run and idle perfectly. I didnt run it very long just wanted to see if it was locked up rod knock etc. I bought this boat because I had a boat that got hit by a car with a 302 Ford in it and was planning to use the motor. My challenge is that the motor I have has rear mounted risers while the motor that is in the Stingray has center mounted risers. I want to use the manifolds off of the known good running engine to see if the one in the stingray is still good. Is there a way to use these? Is there a conversion kit? I have attached a couple pics

 

[kenny nunez]

Is the other engine a Mercruiser or an earlier OMC?

 

[race24x]

They are both 89 Ford OMCs I believe, unless someone changed something. Both have OMC Cobra Outdrives and say OMC on the aircleaner and manifolds.

 

[Lou C]

I looked in the OMC parts catalogs on Crowley marine and the 89 + 90 use the rear exit manifolds and the 91 & up use the center riser style. You will have to look and see if the parts you need are still available. If you can't get them from OMC/BRP then try Volvo Penta because they also used this engine with the center riser exhaust. I did that when I converted my '88 4.3 V6 from the bat wing one piece units to the center riser late OMC/Volo style. There were shared parts between the two from 1994-1998 and some parts used by OMC may still be available from Volvo. Some aftermarket companies may also make them...check around...

https://www.crowleymarine.com/johnson-evinrude/parts/56116.cfm?mdl=TMV29H
example...see the upper exhaust pipe that connects from the elbow to the Y pipe, OMC lists it as not available....

get the part #s of the parts you need to use those manifolds and check on a V/P website for parts (there is one connected to iboats) sometimes the part #s from OMC to Volvo are actually the same.

 

[Scott Danforth]

Buy new center rise manifolds

 

[froggy1150]

Can check barr marine

 

[Lou C]

You certainly can use Barr Marine for manifolds & elbows but the exhaust pipes that mate the 4" elbow exits with the 3.5" OMC/Volvo Y pipe have to be factory parts. Some aftermarket companies like GLM may have made their own version of this part. Mixing and matching can lead to leaks. If you can't find OE at a reasonable price punch in the part number on Ebay or look on NLA marine, they made a lot of these and a good freshwater used set would be fine to use and a lot cheaper. In fact the exhaust pipes I took off my Cobra when I converted to the 2 piece exhaust are still in good shape even with 15+ years of use in salt water.
the ones in this pic I think are GLM....

 

[race24x]

I have a set from a known good 5.0 Ford that are rear riser manifolds. I spent a couple hours last night taking everything apart and they do look like they will bolt on and if I use all of the other boats parts fit onto where the center risers where. What is the difference between center riser manifolds and the ones where the riser is on the end. I will take some pics tonight. I cant see any reason why they wont work.

 

[race24x]

Here are some close ups