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The Critter II

4K views 29 replies 12 participants last post by  sgtfroggy 
#1 ·
Picked this '70 GT up last weekend, I will document the project here. My plan is to keep it mostly stock, but make it a driver not a show car. I have a '73 with a ton of rust which I was slowly repairing, and planning to drop an electric motor in, which will now be used for parts. This GT is already running and has pretty much all the parts, so I am currently planning to keep the original motor.The whole car has been rattle-canned black, but besides the passenger headlight there does not seem to be any significant rust!
 

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#4 ·
Is that the one that's been on the market for over a year with the "Flintstones" floorboards?
 
#5 ·
Nope, I have seen that listing though!

Spent several hours yesterday going through the brakes. Rear driver's side was binding so it could barely drive without spinning out. After pulling it apart and putting it back together a bunch of times I finally realized it needed grease on the contact points. It can now drive without spinning or stalling out (at least at low speeds).

Unfortunately the brake pedal now goes to the floor. I was planning to flush the brake fluid, but when I had the caliper off, pumping the brakes did nothing. I pulled off the brake line from the master cylinder, and the first couple pumps got some fluid out, but then nothing (reservoir was full). Pretty sure this means I need to rebuild/replace the master cylinder. Planning to take it off today and see how the bore looks. I have a Geo Metro booster/cylinder that I may try to swap.
 
#10 ·
Carb is back on. Both throttle linkage grommets were missing; this combined with a super thick rubber floor mat was keeping the secondary butterfly from ever engaging and it was a little stuck. Forgot to add the driver's side grommet to my order from OGTS, so I 3D printed a replacement which is working well for now. Also got some hoses put together for the valve cover/"PCV" vents.
 

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#11 ·
I did a test to see if it's possible to remove the horrible spray paint without badly damaging the original paint. The spray paint covers everything, including most of the engine bay. It has lots of bad runs and is chipping off in many places. I used a product called Krud Kutter Graffiti Remover on one of the headlight housings, and it seems to work pretty well. Once I find a better scraper I'll continue testing.
 

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#13 ·
I have to use a scraper with it. (Actually so far I was using a piece of a coffee can lid.) It doesn't seem to be noticeably damaging the original paint, at least I haven't seen any coming off at all. It might be causing some scratches, but my plan B is sanding it down to the metal anyway.
 
#14 ·
A sharp edge plastic putty knife might be just the trick. They work great on well painted surfaces without damaging the paint. They also make plastic razor blades that could be placed in the scraping side of a box cutter that would work.
 
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#15 ·
FWIW for smaller components I've found that Eastwoods rust dissolver works fantastic I let the parts soak over night or 24 hrs and all the paint peels and wipes right off and the stubborn stuff can be taken off with a wire brush or wheel :yup:
then I strain the product back into the bottle for future use HTH
 
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#18 ·
First, Welcome to AZ, you will like it 8 - 10 months every year !
I talked to Doug / slracer today, IIRC you are now in our extended neighborhood.

When I bought my GT close to 30 years ago it was Black, had been Orange before that, but Gold from factory.
So the engine compartment had also been repainted twice, but without much prep ( sanding ) so paint was peeling there.
When I restored the GT I tried scraping these 2 layers, but what worked best without damaging factory paint in all those places
around the engine etc. was duck tape wrapped around 4 fingers, sticky side out. Press the tape against the surface, pull the
old paint off with NO harm to factory paint. I recommend 3M Duct Tape, cheaper tapes are available, but 3M is best IMO
 
#19 · (Edited)
Need help! I did a tuneup of everything past the coil, adjusted the timing and carb, and everything seemed to be running pretty well. Yesterday I drove it a couple miles to the chiropractor. 10 minutes later, it started back up fine, I made it halfway down the block and it died and wouldn't restart. I tried cranking it for a while, and a couple times it started to fire up, but if I gave it any gas it died instantly. Does this seem like a vapor lock issue? I have a clear fuel filter before the carb, and it had gas in it. Sometimes when cranking it, there was fuel entering the filter, but sometimes it was not getting fuel or there were bubbles entering the filter. After cranking a bit I pulled the fuel line off the carb and it sprayed out a little with what seemed like good pressure. I kept trying to start it over about a half hour period waiting for a tow and nothing seemed to change.

Any ideas what my problem is, or where to start lokking? I haven't tried to start it since then since it's on a trickle charger.
 
#20 ·
Hit it with some starting fluid or pour some gas down its throat. If it fires you will know it is a fuel problem, could be the pump. Just an easy place to start.
 
#21 ·
Gas, fuel, compression. Try Jeff’s suggestion. Sounds like the fuel delivery from your description. If spark & compression check out (Compression is probably fine if you had it running already).

Gas:
I’d start at the inlet to the fuel pump if gas should dump out at a pretty good rate. Install a tee and check the fuel pressure between the fuel pump & carburetor for close to 3 psig. If it’s the stock mechanical pump and it’s old my money is on that. The gas tank plugging up indicated by weak flow of gas before the pump.

Spark:
I usually check spark by removing all of the plug wires off the plugs keeping them away from any metal (ground) securing a spark plug wire around an 1/8” away from the side cam cover bolt and crank the engine (don’t hold it) I usually find a safe way to sandwich it underneath a little block of wood or something, you should see a nice blue spark.
Lastly the carburetor, most inspections can be done without removing it.
 
#22 ·
Jon I realize I never answered your question about the use of Goof off having any effects on the original paint. I use a plastic scraper along with applying the Goof off with a rag and vigorously rubbing, then use the plastic scraper. The over spray chips off leaving the original paint untouched. Have you had any success?
I would agree with Jeff, sounds like a fuel issue. Have you ever replaced the fuel pump? By the way, what did you pay for that 1970 Opel GT?
 
#23 ·
The Krud Kutter worked well initially, but there were some spots that wouldn't come off without a bit of scraping, and the scraping took off some of the original paint. I'll try Goof Off at some point, but for now paint is taking a backseat to getting it running better. I picked it up for $2200.
 
#24 ·
I pulled the inlet to the fuel pump and gas comes out in a steady stream. I pulled the hose off the carb and it comes out pretty fast while cranking, so I think the pump is ok. I can get it to start and somewhat idle, but if I touch the throttle it dies pretty much instantly. It actually ran the best when I had the fuel line disconnected at the carb, I don't know if this is just coincidence or not.

Does anyone know where to find a good description of how the choke operates/latches? I'm not sure if it's working how it should. It doesn't seem to be closing, so I may just need to re-adjust it.

Not helpful that it's over 100 degrees out now and I don't have AC in the garage.
 
#25 · (Edited)
I have the choke plates removed from mine. Especially with the hot weather you’re describing it shouldn’t be that critical. Vacuum leaks are at the top of the troubleshooting list if you have good cranking compression and spark.

I do use the fast idle cam on the choke assembly to assist with cold starting but the cover plates aren’t needed. That said I live in a warmer climate.
Let’s put the choke assembly aside for a minute.
Have you tried using the other adjustment screws yet?


Do this before you chase a vacuum leak.

The choke:
The choke has 3 hex head screws located on the white plastic choke cover if electric, it may be metallic if you have a water choke. Loosen those screws a little and turn the cover, you should do this when the engine is cold you’ll see the choke plates rotate (rotate until they’re almost until they’re close) once you have found the right direction to turn it. Don’t worry, if it’s the water choke the only thing underneath the cover is the BI metal spring. The choke fast idle screw slot faces the front of the vehicle. You’ll want to be sure that it’s not affecting the idle speed after the engine is warm. It should be adjusted while the choke plates are almost all the way closed and the engine is cold.
 
#28 ·
Finally think I made some progress. I measured the compression for another data point and got between 145-155 in all cylinders. I think the issue may have been the float or the float valve sticking closed. I got some starter fluid and it started fine with that. On its own it would sometimes start and run ok, and sometimes start and die. I gave the carb a decent whack near the bowl, and after that it seems to be running ok. Still need to run it longer and try a test drive. If this was the issue, is there any way to prevent it happening again? I just replaced the float valve, but not the float, before I had the problem.
 
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