Slant won't start!!?!!?!?

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sdahmer

sdahmer

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So I need help... once again. My 225 won't start after possibly overheating it last week. I was driving home (uphill) and my temp started climing and the gauge went to about 3/4 of the way. Then it went to 0 as I pulled to the side of the road, turns out the temp sender wire came off. Along with that, the damn radiator fill neck blew off! Yup, blew off! All the coolant/water gushed all over. After letting it cool, I tried starting it and nothing. I replaced a few things before this (starter, ballast resistor, points to electronic, wires, cap, rotor, coil, battery). So now the engine will turn but won't fire up. I don't know if this is right but I used my timing light on each plug wire to see if it was firing and the light lit up on all wires. I can also see gas squirting in the carb if I pull the throttle. Does it sound like it's just a timing issue or could I have blown the head gasket and lost compression? The oil looks fine, but loosing the radiator neck got rid of all the water. I'm just so frustrated and bummed that it's hard to think straight. Thanks for your help in advance!
 
Are you getting coolant out of your exhaust pipes? That would be a sure indication that the Head gasket is blown.
 
Probably the head gasket. When you crank it over, does it sound the same? I once had a VW that I overheated and after it cooled down, it sounded like I was cranking it with no spark plugs. Zero compression.
 
Try turning the engine over by hand (tug on fan belts). If you feel 3 strong "air springs" each rev for 2 revs, that bleed down slowly, you know you have great compression. If not, try cranking it faster with a compression gage ($15 kit Harbor Freight). Don't keep pushing the pedal or you will flood it with gas (each push is a squirt). If you do flood, hold the pedal to the floor and crank to "clear flood".

Your timing light test is a good indicator that the spark is getting to the plugs. Make sure there isn't water down in the spark plug tubes to short it out though. You could also try an in-line spark tester ($4 at HF). Try spraying starter fluid down the carb throat too.
 
Thanks guys! I really appreciate your help. It's hard to work on it right now because it's on the street (I'm currently fixing my salvage pickup in my garage).

Coolant- It all came out when the radiator neck blew and evaporated thereafter. I didn't see any smoke from the exhaust at any time, neither before or during pulling over and shutting down. I did fill it up after with water and cranked it quite a bit, still no water in oil.

Plugs- I pulled them and they're white but no moisture or oil on inside (electrode) or outside. Gap is also correct.

Distributor- I pulled it to check the air gap and gear, both ok.

Timing-I pulled the plugs so I can turn it by hand and use a piston stop to find tdc and compare against original mark.

Compression-I have an old style gauge (push-in) What exactly am I looking for?
 
#1 unhook coil.
Confirm u have fuel spraying in the intake.
do a comp test, look for consistant comp on all 6 cly.
Hook up coil, confirm spark.
#5 recheck everything timing, wires points, e.t.c get out test light.
As far as numbers go on comp, i forget because ive been drinking all night:blob:
 
compression should be a minimum of 70 psi with no more than 10-20%variation between all cylinders. i may be a little off on specs but but if all cyl have atleast 70 it should have enough compression to fire and run
 
sdahmer said:
Compression-I have an old style gauge (push-in) What exactly am I looking for?
Click to expand...

Forget that thing, almost impossible to use on a slant. You need one that screws in

You can actually get "some idea" of whether the cylinders have compression by simply screwing one plug at a time into each cylinder, cranking the engine, and listening carefully to the "thump" when compression hits.

If no hard "thump," no compression. If one or more cylinders has no "thump" then that one is dead

Check spark AT one of the plugs. Do this after all plugs are back in and hooked up, and use just one plug out, grounded to the block. The reason you want the rest hooked up is to prevent crossfiring.

Inspect the cap rotor for grease, dirt, moisture, cracking/ carbon tracking, etc.

Also inspect the spark by using a grounded probe, holding it near the top of the coil tower. YOU MUST use the ignition switch for this test, so you need two people
 
I agree that those push-in compression gages are fairly useless. You never know if the problem is the cylinder or your technique. Anybody who has kick-started a motorcycle or pulled a lawnmower cord (old days before "easy-start") knows what good compression feels like. I can feel that on a slant by turning the engine over by hand. Otherwise, try above "1 cyl at time, listen to starter" method. 70 psi sounds like a pretty worn engine, though it should still fire. I recall ~145 psi is factory new and I like to see >110 psi in all cylinders. It does depend greatly on the cam installed.
 
I finally got the valiant in the garage today and found thr following:

No thermostat
Leaking water pump
Some unknown wire where the thermostat goes
Did a compression test with the push gauge and got about 10 psi in cylinders 2, 5, and 6. 20 psi in cyl 1 and 50 psi in 3 and 4. I think it's safe to assume its blown. I'll be working on putting in some new stuff I got: water pump, thermostat, hoses, radiator and head gasket set.

What's the possibility of the head being cracked?
 
Might be cracked, might be warped. I'd be checkin it. Might be time to think about a different engine.
 
Are you sure that your compression gage works and that you can seat it fully in the deep recess of a slant? Did you pull out the spark plug tubes to get a good seal? Do you feel good pressure with your finger? For comparison, home water pressure is ~60 psi (finger over hose feel). I can't imagine how a failed head gasket or crack could take out all 6 cylinders, so suspect your technique first. Sounds like the engine ran fine before. Maybe invest $15 in a Harbor Freight screw-in compression test kit. Slant heads have little problems with cracks that I have read about, nothing like some engines, and boiling over doesn't usually hurt the head.
 
Thanks for your help everyone. I got around to replacing the head gasket and put it all back together. So far it sounds the same when trying to start it, engine turns and no sound of cylinders firing. I used a piston stop to determine TDC and my finger over the plug hole to find the compression stroke. I will try to get compression readings later today for comparison.

Anyone think it might be a worn or jumped timing chain? I had little power before all this along with stalling at idle. Also, I could only rev the engine to 3k. Could I check valve timing without pulling the timing cover? When checking for the compression stroke I can feel compression quite a bit before TDC.

Thanks again!
 
What do you have for a shop manual? There's a procedure in the manual for doing just that.
 
sdahmer said:
When checking for the compression stroke I can feel compression quite a bit before TDC.
Click to expand...
Did you try this before pulling the head off? I am guessing the head gasket wasn't the issue, and why you should try full diagnostics before jumping at something. Get an in-line spark tester to verify spark. Stop fuel flow to the carburetor, to insure not too rich, and see if it will run with starter fluid sprayed down the carb throat.

If the in-line tester doesn't flash bright, suspect a weak spark. You said you changed "points to electronic" just before. What system? Did you verify it is flashing 10 deg BTDC on #1 cylinder. Some of the conversion kits are tricky and you can have problems like "rotor phasing" or the pickup leads reversed.

It is possible to verify cam timing by using a dial indicator on the valve tops, but you need a good, tight setup. I never had much luck with my cheapie one. I need a good goose-neck mount to do better.
 
I have the FSM you lead me to before and the much disliked haynes lol.

I'm really bad at diagnostics which is why I jump into things.
I have a dial but its also the cheaper one. I have a degree wheel as well.
As for the ignition, I pulled it off a 73 volare (stock mopar electronic ignition). It was running after I swapped it and improved the idle a bit but it would stall with both ppints and electronic.
The sticker on the fender says 0 TDC.
 
I haven't had as much time to work on the scamp as I'd like but I did another compression test and got the following.
Cyl
1-45psi
2-30psi
3-90psi
4-85psi
5-85psi
6-30psi

I also bought an in-line spark checker and the little bulb lights up pretty good on all wires. Tried to set it at 10BTDC, 5BTDC and 0TDC but still no start. It did change in sound though and sounds like it fires in one cylinder but barely. Oh, also tried starting fluid.
 
You have 3 cylinders that are to low for them to make power at an idle, 1 2 and 6. may be time to tear into it. You can squirt a little oil in those low cylinder and do another comp. test. If they come up in preasure you have ring sealing problem. If they stay the same it is a valve or headgasket blown or both. 1 and 2 may have a gasket blown between the cylinders.
 
Good news! It started! I decided to try a new head so I hit the yards and found a candidate. I cleaned it up and lapped the valves which resulted in the following:

Cyl
1) 90psi
2) 120psi
3) 90psi
4) 120psi
5) 120psi
6) 105psi

So I think the head cracked or warped but the head cost me less than any machine work so it turned out ok. It's running a little rough though at:
10 degrees
700 rpm
13-15 in/Hg needle vibrates from 13-15

I had the valve cover off and the pcv valve hose is tearing.
Also, I'm leaking a lot of fuel from the charcoal canister/fuel pump area.
 
Great luck. I still don't think a cracked or warped head could have affected 3 cylinders on opposite ends. With the readings you have now it should idle OK. I assume you removed the spark plug tubes and used a screw-in compression gage. If not, you may not be getting valid readings.

Try closing the choke slightly and see if it runs smoother. If so, it is idling lean (common problem). Even better, try spraying starter fluid down the throat while idling. Insure >8 V from coil+ to BATT-. If not, wiring issues. If still running points, you could convert to HEI ignition cheap since you aren't afraid of junkyards. Read posts.
 
I took your advice and bought the hf screw in gauge and I did remove the tubes. I will try the choke test. Thanks for all your help!
 
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