I\'m viewing (and hopefully buying) my Rx7 tomorrow, from a guy off here on the MRC.
My main points of check are these: -
- Check oil
- Check cold/warm starting
- Checking for accident damage (altho I know there is dent from the container when it was shipped over)
- Check coolant levels (is it possible to actually see a split in the AST?)
- Check car docs thoroughly
- Check full working order of everything (ie air con, fans etc)
- Check sound of engine on idle (how is it meant to sound? My old S14 was noise beast on tick over with loud pulsing injectors)
- Check it pulls cleanly to the red line (should there be a small dip as it hit 4500 rpm as the second sister kicks in?)
- Check for smoke from the exhaust (a little is ok, black unburnt fuel, blue oil leaking past the oil seals on the block or tubby?)
- With a dump valve, does the car over fuel a bit (ie pop and bang like my old S14 did)
Is there anything i\'ve missed or should consider? I won\'t get chance to get it compression tested but its only got 32,000 on the clock so I should be safe (touches wood!)
Anyone? :confused:
QuoteOriginally posted by Matt.Wild
Check the oil colour, level of oil, smell of oil - not always an indicator though as it could have just been changed. Look for any strange colours - like green/white in the oil (but sometimes you will get condensation in the oil, which isn\'t normally an issue). If the oil level is extremely low, then the engine may have been starved of oil (very bad), really old oil stinks, oil can sometimes smell of fuel - something wrong with the tune/injectors. Check to see if there is an oil service log i.e. how often has it been changed? Check that the oil pressure gauge goes up when you rev the engine - the gauge isn\'t always reliable but it should move when the revs increase.
Engine should start straight away when cold, it is a good idea to ensure that the car hasn\'t already been started in the morning. Not a good sign if it doesn\'t start straight away. If it doesn\'t start when warm it could be a sign of low compression.
- Checking for accident damage (altho I know there is dent from the container when it was shipped over)
Check chassis rails to see if they are straight - have fresh paint etc. look under the car to see if there is any fresh paint on any of the floor sections - also check if the floor sections are flat (i.e. no buckles).
- Check coolant levels (is it possible to actually see a split in the AST?)
Also check the coolant colour, look in and around the radiator, AST to see if it has been leaking in the past. Also keep an eye on the water temp. gauge.
- Check car docs thoroughly
Yep - look through the service book, MOT stuff etc.
- Check full working order of everything (ie air con, fans etc)
Yes
- Check sound of engine on idle (how is it meant to sound? My old S14 was noise beast on tick over with loud pulsing injectors)
Rotaries should have very little noise in the engine bay on idle, you should be able to hear a slight injector pulse, belts etc. are a little noisy at times also.
- Check it pulls cleanly to the red line (should there be a small dip as it hit 4500 rpm as the second sister kicks in?)
Second turbo usually kicks in 3750-4000rpm. A good test to check for pinging/knocking is to put it in 2nd gear and flatten it from 2000rpm or so - this puts the engine under heavy load, revving quick etc. - check for any pinging noises (if it does - then it is a bad sign as it could have been doing it for some time).
- Check for smoke from the exhaust (a little is ok, black unburnt fuel, blue oil leaking past the oil seals on the block or tubby?)
Should only be a very small amount of smoke at any time. When the engine is stone cold and started, it may produce a little blue oil smoke - a little is ok, a lot is not.
- With a dump valve, does the car over fuel a bit (ie pop and bang like my old S14 did)
Dump valve wouldn\'t cause this
[/list]
Is there anything i\'ve missed or should consider? I won\'t get chance to get it compression tested but its only got 32,000 on the clock so I should be safe (touches wood!)
Comp. test is always a very good idea. Other than the points above - check the buyers guide here: http://www.mazdarotaryclub.com/forums/showthread.php?threadid=256&referrerid=1
Standard with with rotaries is ALWAYS better than modified - unless you know and trust the person/company that has done the mods.
Cheers :)
Re dump valves - why wouldn\'t that cause pop\'s from the exhaust? Surely when it dumps air out to release the pressure off the turbo blades the ECU thinks there is more air in the system than there actually is due to the dump so would add a little extra fuel to go with the air it thinks should be there hence any pops of unburnt fuel?
Thats why it occurs on S14\'s, isn\'t that the same with Rx7\'s?
\'Real engines\' :D use MAP sensors, rather than AFM\'s, may be thats the difference...
Yep - that\'s right Rich. The MAP (Manifold pressure) sensor will tell the ECU what to do.
Popping from the exhaust is usually from larger exhausts (not cat\'s etc.) and if the Air Pump on a rotary has been disconnected.
Well, air con was disconnected and it had a large bore exhaust.
Pops when you do slow speed gear changes.
I take it that is ok? Engine sounded fine and pulled very strongly. Scarily well in fact!
The big bore exhausts will backfire at low revs as my first rx7 did this too, nothing to worry about.
Just make sure you check all paperwork properly as you would do, and anything the guy says which you think you dont understand or find alittle dubious make sure you ask for an explanation until you understand what he means.;)