Top end rebuild has carb & heat problems!

[Anonymous]

Hi Guys,
I just put a rebuilt head & pistons in/on my '63 170. It runs smooth & quiet, but I'm having a couple problems:

1- It gets super hot after running for 3-5 minutes. Coolant is full, so is oil. Oil pump is working fine & water pump is almost new. Not sure if I have the heater hoses in proper locations from pump to heater. Would that make a diference?

2- As much or more blow by from breather as before rebuild. Is this from the heat?

3- Carb won't choke/unchoke correctly, but was working fine prior to rebuild. If I close choke, it will start & run. If I kick the pedal & let off, it won't idle.

Any ideas? Any avice welcome.
Thanks,
David K
'63 Comet

 

[addo]

Are you sure the thermostat is in the correct way? Your description sounds like it's backwards.

 

[Anonymous]

2- As much or more blow by from breather as before rebuild. Is this from the heat?

3- Carb won't choke/unchoke correctly, but was working fine prior to rebuild. If I close choke, it will start & run. If I kick the pedal & let off, it won't idle.

David,

On number 2, could you describe your crankcase ventilation system? Do you have a draft tube, or a PCV valve with a hose to the carb spacer?

Blow by is caused by excess oil pressure. This as well as the heating problem could be caused by having your head gasket in backwards (upside down from front to back) the oil passage and water jacket holes wont line up. Just ask Cobra6.

On number 3 it sounds like (manual choke right) you just need to check the cable clamp (make sure the knob is pushed in and the choke plate is vertical) and then adjust your low speed idle. Do you have a shop manual?

 

[Anonymous]

I was thinking about that, but double checked the exploded drawing in my manual showing orientation while re-assembling. I will take it out completey & see if it helps. Then if that's the culprit, I will but a new one.
Thanks,
David

 

[Anonymous]

The Head gasket only lined up right one way, so I believe it to be correct. My ventilation set up is the non pcv valve set up, with the breather hose going from the front of the block to the back of the air cleaner. Maybe I have too much oil in it, it's always harder to tell when starting out with new, clear oil.
Thanks,
David

 

[Anlushac11]

8)

When you had the head rebuilt did they surface it to achieve a level surface?

Was wondering if Head might not be sealing because head bolts are bottoming out?

 

[MustangSix]

I don't think I've seen one of these engines set up as non-PCV with a hose to the air cleaner. Non- PCV engines usually have a road draft tube and an open element oil breather cap. With only a single hose to the air cleaner you may have a crankcase pressure problem.

Super hot in 3-5 minutes usually indicates zero water flow. Causes could include faulty t-stat, t-stat in backwards, blocked radiator, water pump belt, or possibly the pump impeller fell off (it's been known to happen on rebuilds). Overheat at rest over a longer perios usually is lack of airflow. Overheat at higher speeds usually indicates a gasket problem.

No idle without choke is either not enough idle on the throttle blade or a big old air leak. Try turning the idle screw first.

 

[Anonymous]

Yes, head was lightly resurfaced. I doubt that original bolt holes left no tollerance on the bolt length. Seemed fine during install. I'm betting on bad or incorrectly oriented Tstat.

As far as the the crankcase ventilation, most '62/63 Comets & Falcons I've seen have my set up. 1" metal elbow out of crankcase front connected to a fat, hard rubber hose, connected to a small elbow on the back of the air cleaner housing. Is there some way to modify this set up to the pcv type & not make any permanant mods? I'd love to remove that fat hose.

Thanks,
David K
'63 Comet

 

[Anonymous]

I'm betting on bad or incorrectly oriented Tstat.

Me too!

Is there some way to modify this set up to the pcv type & not make any permanent mods? I'd love to remove that fat hose..

Yes, I read in another post recently you can get a freeze plug to fit that hole, just tap it in (where the draft tube was originally) and use the other grommet in the valve cover. You'll need to pick up an elbow that fits the grommet. Then the only thing left is where to rout it, either to the existing elbow on the air cleaner or to a vacuum source at the base of the carb with or without a PCV.
Also, as Jack pointed out do you have the correct open element oil breather cap?

 

[Anonymous]

Yes, I have the open element breather cap, & that's where some of the blow by is coming from.

My Valve cover only has one opening, no other grommets. Just the spot for the breather cap/ oil filler.

I was thinking about finding a breather cap with the big hose nipple to connect to & run it back to the aircleaner. So I don't need a crank case vent?

Thanks,
David

 

[addo]

I am a fan of the "through crankcase" ventilation. There are two ways to skin the cat:

1. Run the stock breather cap and single hole cover. Install a pipe fitting into the draught tube hole, and run a fuelproof 1/2 or 3/8 rubber hose to the manifold.

2. Run a later PCV type cover with a sealed cap, modifying the draught tube hole to accept a V8-style push-in breather.

Option 1 probably works best with a worn motor, but use a fat tube.

Regards, Adam.

 

[Anonymous]

Well,
I pulled the Tstat & it was in right. I replaced it with a new 180 deg Tstat & that seems to have solved the insta hot issues. Must have been a tired or jammed old one.

I tweaked the carb a little & everything seems to work great now. Got it timed & it runs like it should. It feels good to try something that seems over your head & it all works when you put it all back together. I haven't pulled pistons out of an engine since Highschool, so tearing into this thing that far seemed daunting.

Next stop, dual exhaust.

Thanks for the ideas guys!
David K