Do I need a new engine?

[gruvola]

Greetings, I have a 1974 TX650 which made a bad noise then puked out all it's oil and stopped. There seems to be a hole in the block. Pic below. JB weld and some oil??

Seriously, after putting 500 miles (legit) on the bike on Sunday. It threw a rod, knocked a hole in the block, and puked it's guts all over Florida 301 near Starke at 65 miles an hour yesterday. Thank God I pulled in the clutch immediately when it started making noise and didn't overreact. Pulled safely to the side.

Lots of friends with blocks available. But what years am I looking for? The 74s were different for electric start? compression release before that? the polarity of the rotor stator are different at '77? carbs different on some too but not sure that matters. engine mounts different on some years?

This bike was a good resto with many correct and some after market parts. It has a new wiring harness, rebuilt rotor/stator, I just updated the Windy (?) rectifier and solid state regulator (which are amazing), carbs are perfect and run super, nice paint and a lot of new chrome. So, it's going to be running again, but I'd prefer not to change too much if I can get a block that minimizes retrofit/changes. Any advice on years to look for would be appreciated.

 

[Its been a long time]

Oh dear, much sympathy.

 

[Jan_P]

Would be surprised if not more needs replacing-- It is a major hit
When it comes to engine blocks many different years should fit
I would check part no on the replacement with the one crashed here
If the same number

 

[Its been a long time]

Yes, I would be buying a replacement engine and stripping the one that's blown up to save for spare parts. Quite a bit of useful stuff there.

 

[AUTOMAN]

Get it out of 1st gear next time!

cliff

 

[Raymond]

Sorry to hear your problem, @gruvola, that's quite impressive additional ventilation you've added, but I'm sure you'll get it fixed. However, I'm wondering if you mean block or engine? Not sure if your intention is to rebuild or swap the engine? In these parts, people might mean the barrel casting when they say block?

 

[jetmechmarty]

1974 to 1983. I believe they’re plug and play. ‘81 and later have black paint on them. No points iggy post 1979. I’m confident you’ll be back in business soon.

 

[gruvola]

1974 to 1983. I believe they’re plug and play. ‘81 and later have black paint on them. No points iggy post 1979. I’m confident you’ll be back in business soon.

thanks, that's the news I was looking for.

 

[gruvola]

Sorry to hear your problem, @gruvola, that's quite impressive additional ventilation you've added, but I'm sure you'll get it fixed. However, I'm wondering if you mean block or engine? Not sure if your intention is to rebuild or swap the engine? In these parts, people might mean the barrel casting when they say block?

gotcha, yep, I really intend to just find a replacement engine with a good block/bottom end and make 1 outta 2. I've got a lot of help from friends who know way way more than I do - thank goodness.

 

[650Skull]

@gruvola Run down on the models and changes in both the Tech Menu and stickied in the garage.

https://www.xs650.com/threads/xs650...orkshop-manuals-tech-information-links.30569/

 

[nj1639]

Years '80 through '83 and you could upgrade to TCI ignition.

 

[46th Georgia]

gotcha, yep, I really intend to just find a replacement engine with a good block/bottom end and make 1 outta 2. I've got a lot of help from friends who know way way more than I do - thank goodness.

Sure would love to know what caused the failure. Please keep us posted.

 

[TX650A Van Islander]

Sure would love to know what caused the failure. Please keep us posted.

Shame about your bike. Cool rare colour.

 

[jaybar6]

That is the upper and lower crankcase broken. Is the rod still intact? It could be the piston broke up and the rod is OK, so the crank could be salvaged.

 

[JJames]

Nice XS . You don't see the green to often. I've always wondered about catastrophic engine failure at highway speed. Glad you're OK.

 

[dave_a]

My bike is a 74 too. How many miles on the engine when it let go?

 

[Jan_P]

That is the upper and lower crankcase broken. Is the rod still intact? It could be the piston broke up and the rod is OK, so the crank could be salvaged.

That is what I am thinking also .A valve dropped down smashing the piston
cylinder gone or need work
Conrod falling down ejecting through the casing perhaps smashing around many times

A bore scope through the Spark plug hole is worth considering They are cheap on line
A sudden hit while running sends a shock trough the parts.
The crankshaft has possibly taken a hit also. Needing inspection. They can twist .Depends on the resistance going through
and if the force was perpendicular to the crankshaft.

 

[AUTOMAN]

Toast
save the gears(maybe) and other tidbits.

 

[Raymond]

That is what I am thinking also .A valve dropped down smashing the piston
cylinder gone or need work
Conrod falling down ejecting through the casing perhaps smashing around many times

A bore scope through the Spark plug hole is worth considering They are cheap on line
A sudden hit while running sends a shock trough the parts.
The crankshaft has possibly taken a hit also. Needing inspection. They can twist .Depends on the resistance going through
and if the force was perpendicular to the crankshaft.

Toast
save the gears(maybe) and other tidbits.

All true, but these are tough engines and @gruvola de-clutched pretty quick. Might be the quickest and cheapest way back on the road is another engine, but I would still be interested to see what an engine strip shows up.

 

[46th Georgia]

All true, but these are tough engines and @gruvola de-clutched pretty quick. Might be the quickest and cheapest way back on the road is another engine, but I would still be interested to see what an engine strip shows up.

Yes, I too am always curious about what causes failures. Having raced cars for many years, I've had a few, and as much as I hated losing an engine, I always enjoyed the detective work.