Just arrived with a 1965 289 and a 1973 Mach I - and a vacuum leak solved

Peter C B

New Member
Jun 3, 2019
Indiana, USA
I just joined this resource and want to introduce myself.

I own a 1965 red convertible 289 with a Holly 4 bbl and a 1973 yellow Mach 1.

A couple of days ago I was driving my 1965 and all was well - nice trip around the "long block". A little later my daughter and her friends wanted me to take them for a spin - I was greeted by very hard starting and continuous stalling. I was forced to slip her into neutral in advance of any lights or stop signs to keep the revs up or she would stall.

I went ahead and did the normal tuneup - points, condenser, coil, timing, etc. No good. I changed the fuel filter in the canister under the fuel pump. I double-checked all of the vacuum plugs. All no good. I had to set the idle high just to keep her running. And the moment I put her into gear, she would stall. The only way to move her was to apply throttle as I shifted into gear. This was sad for both of us.

Next day I shopped around for a vacuum gauge. Third try I found one and hooked it up - to be rewarded by a reading of 8 inched mercury. That certainly points to serious problems as it should be about 18-21 at idle. What I read online pointed to a valve timing issue - which led me down the road of imagining that the timing chain had jumped a sprocket. I started to accumulate the list of parts I would need to get in and change the chain and gears and replace all of the gaskets.... But I decided to chase down the possibility of a vacuum leak further - even though I could hear no hissing.

I popped down to the store and got a can of carb cleaner. After settling the engine in at a fast idle I started spraying around the base of the carb. On the right I got a little hint of the engine speeding up and started to get excited. On the left side a squirt drove the engine into a rpm frenzy and me into a frantic dance of joy. She was sucking up carb cleaner like .... (never mind). Upon disassembly I found that the gasket under the spacer was blown, with a gaping stretch of metal-on-metal that was so big it made no noise while at that air was rushing through.

A quick trip to O'Reily's and $14 for two gaskets and I am cruising around again. I am super glad I checked that vacuum one last time before ripping into the timing chain. It would certainly have "jarred my preserves" to spend days and $$$ on that to no avail.

Happy times!
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