b1114p

First things first - I'm a dumbass. Added coolant to under-filled, hot system. I know better. I'm assuming I cracked a head (heads?). Ton's of white exhaust.

Now - moving forward a couple of questions about my options.

Obviously, after tearing down and identifying the damage, I can R&R the thing - doing all the maintenance items along the way - (valve guides, seals, gaskets, TB/WP/Tensioner, etc.)

Mine is a 79 US, all stock 4.5L. No real issues, but a recent compression check showed low numbers on bank 1 (90-60-90-120). Bank 2 was better (142-150-145-140). Blew a fair amount of oil through the breather - blow-by may have been pretty high, car has 161k mi.

Options:
- Can a later engine, say a 4.7L be fitted and use my CIS injection (and associated intake system)? Would exhaust, clutch, wiring, plumbing, mounts work from the 79 with such an engine from, say, an 84?

- Would a Euro 4.5L be compatible?

General question: What are the block markings for US vs Euro engines?

Thanks for any help or suggestions...

Ben
79 928 #275

soontobered84

M28/01 (5 speed) or M28/02 (AT) for the 77-79 Euro engines
M28/03 (5 speed) or M28/04 (AT) for the 77-79 US engines

courtesy of www.928gt.com

go to the tips/links area, then the tech/specs area and look up engine types. Just a wealth of knowledge and information there. Good luck

b1114p

Follow-up 1 - seems like the heads might be okay after all. I'll know for sure once I clear all the oil filling the intake side of the heads...

This may be fallout from installing 928Motorsports oil control system? It went in about 5 miles before this happened. My thought is that the oil separator mod causes too much restriction on crankcase pressure and perhaps siphoned oil up from the pan...

blown 87

While putting cold coolant into a hot motor is never a good idea, it is going to get a lot hotter before it reaches the head.

It is one of those things I have always heard not to do, but in 35 years of doing this kind of work I have never seen it crack a head or a block.

YMMV

Lizard928

While I agree it isnt a wise idea, it will not do any damage to the system due to the routing of the system.

b1114p

Right - guess I kinda spazzed when the car started spewing all that smoke so suddenly. As is too often the case, I drew the wrong conclusion, but hey...

I'd only added about 2 qt. of fresh water to the car and it had only been driven about 1.5 mi prior, so it shouldn't have been extremely hot. My initial assessment was that the reservoir empties into the bridge piping and would have thus been dumped directly into the heads, but I guess the flow should have been in the direction away from the heads(?).

Anyway, I'm piecing it back together after removing as much oil as I could - being careful to not overfill with oil. I'm going to investigate the breather system one component at a time to make sure this doesn't happen again.

Thanks.

SeanR

Can you elaborate on what system you installed, and how you had it routed please?

b1114p

The Oil control system from 928motorsports.com- baffle plate, mod for oil separator (2 weirs), drain tap from breather pipe into L camtower...main breather pipe to existing airbox nipple.

I did have an issue installing in that the washer for the oil separator didn't fit inside the inner "tube" of the modded separator. I sanded down the edges until it would go into the tube without binding.

(Also, I had to supply my own tubing for the camtower nipple and for re-routing the old coolant tubing from the old breather pipe since no splice adapter was included in my kit).

I went back over the installation instructions, but didn't see where I went wrong...I plan to contact them to review this week.

SeanR

Let us know how that works out, I'm sure Carl will try everything he can to help you out. He always does. Usually things are test fitted before hand so it is user friendly, but there are times that just doesn't work that way.

Please post a follow up.

b1114p

I cleared as much oil as I could from the intake ports in the heads and the cylinders (about 2tbsp per cylinder) and installed some clean plugs.

It is running, but I have removed the washer provided with the oil control kit from the bottom of the oil separator... thus the oil separator is (presumably) less restrictive. I'm going to closely monitor oil level and double check what grade of oil I should be running and go from there. I still need to check in with Carl though...