toplessFC3Sman

iTrader: (1)

I'm starting an engine peripheral tear-down on my turbo-vert to correct a number of leaks, clean up the whole engine bay, and in general give everything a good once-over. While I was pulling things apart, I had a few questions. For reference, as far as I'm aware, all the pieces of the engine are S4 T2, although I pulled it out of a field in Virginia with no history & had it rebuilt, so I don't know too much about it.


First, in the above picture, there are the two bosses from the front iron that are sticking up to match the front cover, but the front cover has studs tightened into it that don't extend back to the front iron for bolting the water pump on (so nothing here attaching the front cover to the front iron). This definitely seems wrong, but how was it done originally? Long bolts that went through the waterpump and front cover to thread into the front iron?

For more background, when I was changing the waterpump, the bolt furthest to the passenger side was missing completely, and I know that hole went all the way through the front cover and into the front iron - it seemed stripped so I tapped in as far as I could and used a bolt to try to hold it all together when installing the new pump. I wanted to avoid removing the front cover completely though, and deal with the possibility of dropping the thrust bearing and royally screwing up the engine.


Second, and pardon the mess of gasoline & coolant (just removed fuel rails, and leaking o-rings btwn LIM & keg), but the OMP lines are not staying full. At this point, the car hasn't been run for about 2 weeks. I made sure they were when first starting the car for the season by holding the lever for the OMP up fully for a while, and a few years ago had checked that the one-way valves in the OMP injectors were working (rebuilt the lines & OMP at the same time). Is this a symptom of leaky one-way valves, just something that seems to normally happen, or something else?

Thanks a lot!

RotaryEvolution

iTrader: (30)

1) normal situation, the OE setup is 4 studs to hold the pump housing to the front iron not 4 bolts. studs actually hold torque better than bolts do, as you will notice various studs throughout the car in more important locations.

2) the air pockets are probably due to faulty check valves in the injectors or improperly plumbed atmospheric vent to the thick port at the rear of the UIM near the throttle body.

toplessFC3Sman

iTrader: (1)

Yea, there were 4 studs, one long bolt through the front cover into the front iron (far drivers side, holding the alternator adjustment arm too), two short bolts, and one missing that I temporarily replaced with a bolt until I can get to the store to get a stud the right size. I know you want to use studs, especially when threading into aluminum since it strips much more easily - it just seemed that if there weren't studs or bolts going into those raised bosses on the front iron in the first picture, then they served no purpose, which just didn't seem right.

I'll pull the other oil injectors and test the check valves then. Right now the "vacuum" source they're hooked up to is the top nipple on the back of the UIM (only 3 nipples in a row on the back, IIRC this means it was a JDM UIM since USDM had 4?), which is feeding from the intake pre-throttle (atmospheric to boost). Is this correct?

Thanks a lot!

RotaryEvolution

iTrader: (30)

i see the studs for the water pump/housing in the picture, unless the question is about something else.

toplessFC3Sman

iTrader: (1)

Yea, the studs are there in the picture, and they're threaded into the front cover. However, behind the hole in the front cover that they're threaded into is a raised boss sticking up from the front iron. It seems that if the studs are threaded into the front cover (as they currently are), why would the front iron need those bosses?

Put another way, just looking at the way the front cover & front iron are shaped there, I would expect something to thread into the bosses on the front iron, pass through the front cover, and get tightened on the waterpump housing, sandwiching the front cover instead of tightening into it.

RotaryEvolution

iTrader: (30)

the water pump housing studs are threaded into the iron, not the water pump housing, they pass all the way through it.

none of the water pump studs or bolts do anything with the front cover and are independent of it completely.

the pump should slide right off after removing the 4 nuts and long bolt for the alternator adjustment arm. a lot of the time silicone or rust get it jammed up and it has to be pried off.

toplessFC3Sman

iTrader: (1)

Ah, ok - I had thought they were one piece initially since the housing seemed pretty stuck. Got it off today though, sorry for the confusion.