help fixing an old mercury (1 Viewer)

[semlin]

basic mechanic 101 problem here. What causes intermittent loss of power and white exhaust smoke in an old motor after it warms up? Since it is an i6 I thought I'd ask the cruiserheads.

trying to help get my brother's 1966 mercury comet going. 200 i6 motor. one barrel carb. We have recently replaced pcv valve, plug, points, condensor, rotor, cap and leads, and the radiator. It was in storage for 9 months. It runs great except that it is intermittently losing power (won't go over 25 mph) after it warms up and generating a lot of white (not blue) exhaust smoke when this happens. No noticable misfires, shakes or rattles (it had those in spades before we changed the plugs and leads), just a loss of power. Any suggestions? Between maintenance on my 80 and outboard motors, I know just enough to be dangerous. I was thinking fuel system except for the white smoke.

A couple of months before it went into storage he was having stalling problems caused by tank flakes getting into the fuel filter, but they appeared to have been fixed. He paid a shop to have the carb rebuilt, new fuel filter, lines blown out and the tank was lined with something. We have checked the fuel filter a few times when the symptom shows up. Apart from a small chunk of epoxy in it the first time, it is clear. I was thinking maybe the old gas was stale but it has fresh gas in there now and the problem persists.

This a nice old car with no rust and is very easy to maintain since it is a true poverty model with enough left over room in the engine compartment for a family of 5 to live.

 

[fsusteve]

First I thought you were talking about Merc outboards, so I was gonna say buy a Yamaha

Anyways, is it running hot, loosing coolant? Could be a headgasket with those symptoms. Or running really, really lean.

 

[semlin]

thanks, I had eliminated that because it initially did not appear to have used fluid, but judging by the lack of fluid now (down 2 litres) and the fact it started missing, it's the head gasket alright.

So, can anyone recommend a good book or website where my brother and I can learn how to do a head gasket on one of these? I suspect we will never find an easier engine to learn on.

 

[PHAEDRUS]

I have the 1966 national service data volum on my desk, pm me and I will drag it home, I have the official Ford manuals form 71 on I can drag it as well if needed.
Dave

 

[Landpimp]

me too, was thinking boat motor

and yep Yamaha's I got a pair(130 and 9.9) of em

First I thought you were talking about Merc outboards, so I was gonna say buy a Yamaha

Anyways, is it running hot, loosing coolant? Could be a headgasket with those symptoms. Or running really, really lean.

 

[semlin]

Actually I own an old suzuki outboard, and they are way more reliable than yammies.

plus I have old 70hp merc o/b hulk if anyone wants it?

 

[Junk]

shoot the bitch then set the frickin thing on fire and roll it into a lake dude.

 

[semlin]

Hey Junk thanks for the constructive help

we pulled the head last night in about an hour starting from scratch. Wow is that ever an easy motor to work on. the gasket had gone at #5 and #6 cylinders (sound familiar cruiserheads?). There was a little bit of coolant in the #5 cylinder but not much. Can't tell if it has leaked through or not but it does not appear so.

Lots of carbon build up on the cylinders. Anyone know, can I use brakleen to get it off or do I need to use something gentler? Also, I am assuming scotch pads are ok to clean up the block surface.

We are dropping off the head today to get it shaved and will try to reinstall tonight. I am not sure if there is anything else worth doing while we are in here. There is lots of carbon build up in the head chambers leading to the manifolds but it seems pretty tricky to clean out.

 

[fsusteve]

Just stick a 200 Yamaha in there and be done with it, it'll run forever.

 

[semlin]

Thanks Steve, but I'm not sure if we want a car that burns 10 gallons per hour and spews oil out the exhaust.

 

[semlin]

betraying total ignorance again, but what can we safely use to clean the mating surface on the top of the block and the carbon build up on the cylinders. In the back of my brain I am thinking you can't use solvents like brakleen because they will wash into the motor? CAn I use a paint scraper or scotch pad what exactly?

 

[fsusteve]

Thanks Steve, but I'm not sure if we want a car that burns 10 gallons per hour and spews oil out the exhaust.

You must have tweaked it to get that kind of fuel efficency

You can get gasket removing scrapers at NAPA or any other parts store, they also sell gasket remover spray and a little gizmo that goes into a drill that works pretty well.

 

[Junk]

Hey Junk thanks for the constructive help

Any time

 

[semlin]

Hey junk, are you sure your karma is so good it can survive mocking a guy fixing a head gasket

BTW, the head gasket is back on and it runs great. That was actually fun. Not that I want to do it again on my 80 but that is one less thing to be deathly afraid of.