So while i was farting around with my coolant system the other day i put in a stant thermostat (DONT EVER BUY STANT) The thermostat didn't open until the factory gauge on my S4 hit H. Yeah i know it was my fault, i have an oem thermostat now and it works great but its kind of too late. Anyways my car puffs smoke like a train now (sweet smelling, hard to start in the morning, and puffs smoke as soon as it starts.) Its got to be failed coolant seals.

I found a 13B S4 NA for $900 with fresh seals and apex seals just rebuilt and its also half bridgeported. Should i pick this up or go for a jdm/usdm s4 turbo? or maybe a FD engine?

Thoughts ideas? It is a track car only that will get minimal street use for driving to tracks etc.

My car is a base s4 with a swapped 5 speed

Dennis

 

A Bridgeport should be fun!

 

A Half Bridge probably won't be too nice to you as a DD in terms of MPG's but it would definitely be fun to drive..

 

$900 is cheap. Cheaper than a rebuild. Find out who built it, and if they are reputable, buy it.

 

That's sketchy cheap. Half bridge will be mad fun and not a street car. But if you do street that people around you will **** to the brab brab brab

 

Rebuild it yourself and you know what you have !

 

So guys i did a compression test and coolant leak test and it holds psi and 100 compression on each rotor. wtf why is it smoking, i put transmission fluid in the engine about 50 miles ago don't tell me that's still smoking?? For some reason now it only smokes above 4000rpm

 

Would you still get the bad smoke if your seals where blown in the rotors?

 

It's either coolant seals or oil seals

The easiest most fail safe way of testing coolant seals is a head gasket block tester from napa
They're like $40 and you can use em for years

It's basically a chemical dye you put in supplies glass beaker.
It sits on where the pressure cap goes

It's starts out as a yellow fluid and if it senses the presence of exhaust gas in the coolant system it turns blue, pretty easy

If you're still making good compression a rebuild could be as cheap as 5-600 dollars if you didn't crack a coolant jacket,
even if you did it still could be done for under $650 if you are able to reuse hard seals and source a cheap iron

 

faulty coolant seals usually act as a one way check valve and sometimes won't show up on a pressure test. they can leak one way and not the other, sometimes both but not in most cases. sometimes the engine will not ingest coolant but the cooling system will overpressurze and overheat or push coolant out of the system regularly. if the break is on the intake stroke then the vacuum will pull coolant into the engine and burn it off and fill the engine as it cools, resulting in hard starts and running on 1 rotor until the coolant burns off.

if it's smoking TM is correct, it is oil or coolant seals. if it smells sweet then it's most likely coolant seals.

worst case it has a fractured iron coolant seal wall and will require repairing one/multiple cracks or replacing the faulty iron(s). rebuild parts cost $500 and go up from there.

be weary of any rebuilt engine, even those built by reputable builders. the engine may have been built properly but the build is only half of the equation, faulty installs can kill an engine just as quick as a poor rebuild. if you have a spare daily driver and the tools you can rebuild it yourself for less than the engine you are looking at. n/a engines are nearly bulletproof if you make a note to keep up with the important points, such as cooling system functions. the only reason your engine likely failed is due to the coolant seals being 25+ years old and rotten already.

 

Do it yourself! It's not that hard and if it's only the coolant seals it'll be an easy rebuild.

 

Excellent advise Ben. This needs to be framed