Reddit mentions of INNOVA 3612 Compression Tester - 4 Piece Kit

All of this is fantastic advice. Spot on. I'd like to add a few items for examining ads, looking at the bikes themselves, and tips to avoid being stuck with a lemon.

1. No bike that isn't running should sell over 500. 1000 is right out. If the ad says it only needs a battery, ask if they have a dead battery to jump start the bike and hear it run. When you look at a bike that doesn't run, you're taking whatever the seller says on faith. You don't want to buy that battery for your new super cheap bike just to find the engine is chewed up inside or the chargin system is shot. If it doesn't run, assume it's a rebuild project and walk if you're not ready for it.
   
   
2. Always do a compression test. This goes double for anything more than ten or fifteen years old. A clever seller will clean and wax that bike to perfection and tune it to make up for any inadequacies the bike might have mechanically. A gauge isn't too expensive and will tell you more about the bike than the condition of the paint and chrome.
   
   
3. Check for suspicious tuning. Tell the seller you expect the bike to be cold when you get there. Even a lousy bike will start nicely when it's all warmed up. Check the idle speed. Look up the idle speed for the bike online and figure out what it should be. A little variation is fine, but if a v-twin cruiser is idling at 1500 rpms even once the choke is taken in, there should be a reason why. Cranking the idle speed can help hide bad carbs or even valve problems. Don't trust it.
   
   
4. Take a look at the fluids. If ithe oil is super clean they did an oil change for the sale. This doesn't mean you should walk, but it does mean you want to take a closer look. On one hand they might have just done the change as a matter of course or as a courtesy to the buyer. On the other hand, they may have wanted to hide the fact that the oil has metal filings in it from soemthign getting eaten up in the engine. If it's water cooled, and the radiator has a fill cap, open it up and dip a stick in. Murky can be ok on old bikes, but any sign of oil in the coolant speaks of a failing head gasket.
   
   
5. Assume any information about needed repairs is shakey at best. If a seller advertises a bike in perfect shape, and you point out something wrong, they should not back pedal with soemthing like "Oh my mechanic friend says it needs a new something or other which is really cheap and easy to do yadda yadda ya..." If they knew the bike needed something, it should be mentioned up front or in the ad. Not saying anything about it could be a sign theyw ere hoping you didn't notice, and casts whatever they say the repair is into doubt. If you go to look at the bike and a seller tells you up front about needed repairs, that's fine. Just don't tolerate any attempt to hide something.
   
   Good luck looking for bikes. I hope this helps.

Not an expert, but

I'd focus on the drive train issues first, get all those tires working, might be a lost cause before going any deeper, but others will have to help with that, I take that kind of stuff to my mechanic.

Brake pedal could be that it's low on brake fluid, or one of the brake calipers is stuck.

My quad has a foot brake like that and a hand brake, but the foot brake only brakes 1 tire. That tire has two brake calipers on it's roter, one to the foot break and one to the hand brake. So the hand brake is all 4 wheels, and the foot brake is 1 wheel. There is a master cylinder on my hand brake and another on my right rear tire (foot brake). If my foot brakes master cylinder runs low or springs a leak, my pedal goes through the floor like in your pic but I'll still have brakes on the hand brake. It's like a double/emergency braking system. If my hand brake goes out I can down shift (engine brake) and lay on that foot brake to brake and not hit a tree...
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Fuel wise, it's likely carburetor being old. The carburetor should have a primer on it that injects gas into the carb when you press/pull it. Those generally have a diaphragm in them (rubber) that tends to go bad over time and cause a fuel leak.

If you can find a diagram of the carburetor that would help emensely.

Really though, you should take the whole carburetor off, take it apart and give it a bath in carb cleaner (no plastic/rubber in there) and clean all the jets out.

Also, they make rebuild kits for most carb's that come with all new jets, and pilot screw etc. See if you can find one. I typically just replace them all, easier and then I have spares.

Also, inspect the carb's vent hose and make sure it's intact and not clogged. Check the fuel line too, for damage/rot.

You should also remove the gas tank and clean it out. Take the petcock off and inspect the filters and valve, then clean the whole gas tank out so there's no dirt/bad gas in there.

Then check/change the spark plug(s). Before running it though, I'd check the valve clearance on the valves, guides on that online.

Once all that's done, it should run good and not leak gas.

Then you can address your other issues.

Pending how old it is, there are some parts I might replace just because:

• Voltage Regulator
  
• Starter Solenoid
  
• Starter
  
  If the current ones are working, call them spares.
  
  Starters and solenoids are cheap, voltage regulators OEM are expensive, but you can buy a few after markets pretty cheap to have spares.
  
  Tool wise, I can recommend at least the following:
  
  
• Wire/Brushes
  
• Jack/Lift
  
• Compression Tester
  
• [Feeler Guages] (https://www.amazon.com/gp/product/B000BYGIR4) You want these to go from at least .002 to .014 inches
  
• [Caliper] (https://www.amazon.com/Neiko-01407A-Electronic-Digital-Caliper/dp/B000GSLKIW/) If you need to measure float height, you want to be accurate.
  
• Angle Finder Useful for float height, as most carbs need to be held at a specific angle for accurate float height adjustment.
  
  Then your typical ratchet sets, air tools, impact guns, etc.
  
  And socket extensions (long ones) because getting to some things is a royal pita.

With something like this. https://www.amazon.com/Innova-3612-Compression-Tester-Piece/dp/B000EVU89I

Often you can rent or borrow these from shops or DIY garages. For the testing itself; any youtube tutorial will do. I personally like to watch chrisfix.
https://youtu.be/PNhuDCVIydw

From what I hear, miata engines seem to be pretty solid even at high miles. That being said, it depends on how the owner drove and maintained the car. When you're looking to buy, ask the owner if you can run a compression test on the motor. They're pretty cheap for what they can tell you.

Oh boy...

Compression test it. Google it. Cherokeeforum.com, naxja, etc. This isn't really the place to get any kind of tech advice. Not even close.

I don't really feel like getting into all of this tbh... but for starts oil leaks don't = burning stuff. That makes no sense. Oil leaks, blowby, and burning oil are all just part of the life of a 4.0. Burning coolant is no bueno. It will wipe your engine eventually.

Compression testing is the first step to see what your engine is doing internally.

Don't buy the HF compression tester. It sucks balls. Trust me.

this one is actually very good for the money. I trust it. Seemed to work fine on my civic, gmc, xj, and snowmobile.

Even if your engine is totally fine, you need to address the heater control valve and VCG - but it's a good idea to comp test as well.

It was a bit of work, but the compression check is super simple and if the compression is bad then you don't need to fix anything else until the compression is fixed. I got my compression tester from Amazon https://www.amazon.com/gp/product/B000EVU89I/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

And Re: the vacuum line yes, that line on both ends with the rubber boots is good. I saw that they crack easily but mine are both pliable and the rear was REALLY hard to remove (had to check it out) so it was snugly on there. I checked all the small vacuum lines and the boots all look good, they all seem to be in the right places. There is a line in the very top right corner (look for the green connector) that goes from there to the right side of the intake that is somewhat brittle, but messing with it didn't seem to affect the engine performance at all.

I have to think this is all pointing towards timing considering what you've said and what I've read about O2 sensors and vacuum leaks. I will order up the compression tester if you think that is worth it .. seems like I may need a special fitting for the 5.4l Triton engine and it seems like it might have narrow plug holes? I see that OTC and others sell a specialty adapter but others on Amazon seem to just have a long hose with adapters anyhow.. so would those work?

http://www.amazon.com/INNOVA-3612-Compression-Tester-Piece/dp/B000EVU89I?ie=UTF8&psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=ATVPDKIKX0DER

http://www.amazon.com/INNOVA-3612-Compression-Tester-Piece/dp/B000EVU89I/ref=sr_1_1?ie=UTF8&qid=1463577640&sr=8-1&keywords=compression+tester

https://www.amazon.ca/INNOVA-3612-Compression-Tester-Piece/dp/B000EVU89I/ref=mp_s_a_1_5?keywords=compression+tester&qid=1563192308&s=gateway&sprefix=compression+test&sr=8-5

Or pick something up from your local Canadian Tire.