First Post!!!  Been reading plenty though.  So I have a 71 429 BBF super cobra jet.  Had a leaking intake by the disty so I took off, replaced gaskets and sillycone and slapped it back together.  I “think” I timed it correctly, but could need to revisit that. While I had it apart I attempted to resolve the issue of oil misting out of the pvc (passenger side rear) and breather on driver side by routing both valve cover breathers holes to a catch can.  I then routed the catch can to the vacuum port on the back of my Holley 700. I got worried about too much oil getting to the vacuum so switched the to a breather off the catch can and a plug on the vacuum.  The boat fired right up and sounded great!  But it would not quite run right.  Figured rough idle cold could be due to the PCV/vacuum delete.  I was able to get it warm and idining well around 1300RPM which is as low as it ever idled, (it does have a cam) but then it got HOT.  Blew out/melted the rubber water exhaust hose going from the snail to the transom on the passenger side... TWICE!  Starting to think I have a problem.  The intake is leaking in the rear as well again, so I am going to re do the intake this weekend.  I also fear someone may have altered the intake, there are machining marks on it that do not look factory... but it ran well before I tried fixing my intake oil leak the first time. 

Lots going on here, I know...

1. Retarded timing WILL make the exhaust hot. Make sure it's right. I'd static time it at 10°.
- Rodger that! 

2. We're you running water at the time?
Those hoses, yes the expensive exhaust hoses are water cooled.
- always has good water flow, I am in a shallow lake and am not 100% sure I didn’t grab some sand while timing on my lift..(yes I did the overhaul on the water). Boats out now so I will confirm good flow.  Any one know how shallow recommended operating at start up is?  I understand I can cruise through shallows, but have heard rumors that these things can suck sand from 6 feet down, possible?

3. Sounds like the engine has a fair share of blow by. The intake seal at the china wall might not ever be sealed.
-should I keep fighting that battle or concede a little oil leakage?  I was considering getting both a .6 and a .125 intake gasket this time around to see if perhaps I inadvertently switch thicknesses when I did my last repair.  I used an edelbrock .6 not sure what was on before it came off in pieces.

4. 1300 is quite high even for a big cam. Possibly a vacuum leak leaning it out.
-I’m suspicious of his too, how do I seal a leak if one is discovered? Will test with carb cleaner.

5. How is the cooling system plumbed? Water from the jet, to the logs, out the logs to the water pump block off plate, out the t-stat housing, to the snails. Make sure the cooling hoses aren't smashed or kinked.
- I will confirm and document all of this.

THANK YOU!!



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Not sure if it’s just getting stopped at the snail, but no water out the back.  Log is ice cold though so there is water flowing that far...


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Sounds like either the hose from the t-stat housing to the snail is blocked, Or the snail itself is plugged up with sand and corrosion.

Easy to diagnose, pull hose at t-stat housing and flush with the hose.

Dan'l

Got a noise on the side that was blowing boots now... think I cooked something


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