shotglass_10

i took out a plug for each cylinder and the front cylinder seems to be getting excellent compression, but the rear cylinder is much lower it still compresses just not as much as the front, any suggestionss? also is it possible to put a 13b out of a 93 rx7 into an 85 GS?

mazdaverx713b

iTrader: (91)

wow. cylinder? you must be speaking in hebrew brother. all smart comments aside, you mean front and rear rotor. you'll need to pull both plugs per rotor to get an "accurate" reading. it wont be accurate but with the pssh pssh test, you can determine if an apex or side seal has gone, not actual comression readings. you need to do this one rotor at a time. yes, you can swap a 13b from a 93+ in an 85 GS. almost anything is possible in this world. you need an SE front cover and pan and TONS more. why do you want to do a swap?

southernrunner

Well try putting some sea foam in the carb. That will break up any carbon build up that is on the housing which is possible for causing low compression. As far as sticking a 13b out of a 3rd gen, you will have to modify it to fit. I heard it is a pain but if you have the right tools, time, and money it can be done. Try the sea foam and see if that will help with compression, I used Marvel Mystery Oil and it worked for me. It didn't go to perfect compression but it did go up about 25psi on each rotor. Oh and if you see a whole crap load of smoke, your screwed.....lol just kidding.

shotglass_10

thanks used to piston engines sorry! i did the test to see if the apex seals and side seals were good and it seemed normal the car wont start it cranks and has fired breifly on a few occasions but wont run and im stuck! as for the swap i had a chance to get a 93 13b cheap and was just curious if it could be done but i really dont want to end up in a mental institution trying to swap the engines. any suggestions as to what else could be wrong? thanks.

shotglass_10

sorry never mind ill try the mmo and sea foam this computer sucks it wont display all the page and i missed southernrunners reply nevermind! thanks

mazdaverx713b

iTrader: (91)

are you sure you're getting fuel and spark? check for big vaccume leaks. also, check the front sight glass on the carb and make sure its half full. far over half or far under and you may have carb problems. these are the basics, let us know what you find.

shotglass_10

thank you guys so much also where can i get the sea foam?

shotglass_10

also i am getting spark and as for fuel i havent had time to check

mazdaverx713b

iTrader: (91)

seafoam can be had at most auto part stores. i get mine from napa

trochoid

iTrader: (6)

Have you changed the fuel filter?

Kentetsu

Possibly flooded. Dump a couple of caps full of motor oil down the small (primary) barrels of the carb, make sure that the battery is fully charged, then try to start her up.

If you get it to run, use a can of Seafoam with 1/8 tank of gas and go out and drive it like you stole it. This should free up any sticking apex seals for you, and clean the entire engine out nicely.

Has anybody messed with the timing since the car last ran? You might also want to try new (leading) spark plugs.

shotglass_10

the fuel filter is brand new the plugs and wires are also i got some seafoam and mmo and am going to try that i tried the oil trick and no go ill post the findings thanks!

mazdaverx713b

iTrader: (91)

did you have a chance to check to see if you were in fact getting fuel?

shotglass_10

yeah i checked and it is all good on the fuel part im currently doing the sea foam treatment and when i turn it over backwards by hand it sticks on a certain spot ive been taking it easy on the spot and using plenty of seafoam it seems to be getting better any idea what is making it stick? i have no idea if the timing was messed with the @$#@ that had it last wont tell me anything about it and he says that whoever gets it gets to figure out whats wrong with it.

southernrunner

possibly thick carbon build up. I was looking at my friends engine while he was cleaning it today and there was plenty of that.