1978 mercruiser 260 questions

[kershawD]

where can I find measurements on different exhaust elbow risers? the manifolds that I have use the same riser gaskets as many others. but I cant find info on the length of the elbow . to get an idea of what im trying to do the photo will help explain it.

 

[kershawD]

electrical brackets on a 1978 mercruiser 260?

I need good clear photos of the electrical brackets on a late 70's mercruiser v8 . my boat didnt have an engine in it when i got the boat and im trying to figure out how they all bolt on.

 

[Bondo]

Ayuh,.... Ya might try the service manual #1, found in the Adults Only section, under Merc Manuals,.....

 

[Bondo]

Ayuh,..... Please keep all yer questions 'bout this motor in 1 thread,....

No need for a new thread with each question, or the back-story gets lost,.....
I'm gonna merge the 2 I've found so far,....

Whatever that motor, 'n manifold is,..... it Ain't a '78 Merc,..... 'cause it would have log-manifolds if it was,.....

The manifold looks Volvoish,.... either way, ya need the cast elbows that go between the riser, 'n y-pipe,.....

 

[kershawD]

thanks. the manifolds are OMC. I would change manifolds but dont know what will work with the exhaust Y . if I can change just the risers and get the elbows and rubbers to convert that would be great and Easy. original logs are unavailable and all center riser manifold kits are not complete kits. no info on what is needed to complete the conversion.

 

[Bondo]

no info on what is needed to complete the conversion.

Ayuh,.... Because it's an unknown path yer headed down,......

Yer gonna have to re-engineer it yerself, with the junkyard parts yer tryin' to put together,....

Volvo manifolds ain't gonna have the bolt holes where they oughta be, for Merc brackets,....

 

[Scott Danforth]

your best bet is to unbolt everything that is OMC and throw it away (leaving the long block). then bolt on everything mercruiser to fit the installation.

 

[kershawD]

I have ditched all the OMC parts. i'm having trouble with finding a complete exhaust kit . I don't have the originals to go off of. my boat does have the original mercruiser Y in it with the 4'' to 3'' rubber reducers that will also be replaced . i also have the original power steering pump with mounting brackets . it bolts down on the bottom of the block. most of the pictures I have seen online don't show the same location . I understand that most exhaust kits don't actually come with all parts and hardware needed to do a complete install, however there must be others that have done it and can make a parts list of everything that's required. from manifolds to thermostat housing, water hoses and hardware

 

[kershawD]

this was from when I first brought the boat home. and started to clean it out. it had a custom boat cover on it when I pulled the cover off black dirt was covering just about everything. the boat registration had expired in 2004. so it sat for a long time .