View Full Version : Lt1 distributor/water pump


Imprl59
02-06-05, 02:24 PM
Well my new '95 Fleetwood has been playing buck buck lately especially around 45mph just after it drops into overdrive. Silly me thought I needed new plugs and wires.

Once I got down there to do the wires I found that the water pump has failed leaking hot coolant on to the distributor. Coolant got inside the distributor causing the miss.

Now I need advice. I can't believe how expensive these parts are but I want to do it right the first time. Should I just replace the whole distributor or is a "cap and rotor" good enough?

Factory water pump or does someone have a new improved model that doesn't fail after 40k miles?

Any "might as wells" that I should go ahead and take care of while it is all apart?

Thax for your input
Steve B.

Katshot
02-06-05, 02:56 PM
IMO, the stock Opti-Spark distributor isn't as bad as a lot of people claim. The distributor isn't even all too bad price-wise either. You can get them for about $220 and I think that's pretty good for a complete OEM distributor. The OEM waterpump is a very durable one too. We used to replace them at about 140K miles with the timing chains/gears as preventative maintenance and rarely had one fail prior to that. The only thing I'd say to check "while you're at it" is;
1. The distributor harness.
2. Ignition coil and coil wire.
3. Vacuum lines connected to the distributor (they're actually vent lines).
4. See the line above about the timing chain/gears.

Imprl59
02-06-05, 07:16 PM
Thanx for the input. This is a 40k mile engine so I'm not going to look at the timing stuff yet but I will go ahead and replace those vent vacuum lines. Where can I get a distributor for that $220 price? I'm looking at $390 for AC/Delco and almost $200 for a water pump.

Steve B.

carguy16
02-07-05, 05:19 PM
I dont know how a water pump functions, but how does the water pump failing cause everything to leak everywhere???



Well my new '95 Fleetwood has been playing buck buck lately especially around 45mph just after it drops into overdrive. Silly me thought I needed new plugs and wires.

Once I got down there to do the wires I found that the water pump has failed leaking hot coolant on to the distributor. Coolant got inside the distributor causing the miss.

Now I need advice. I can't believe how expensive these parts are but I want to do it right the first time. Should I just replace the whole distributor or is a "cap and rotor" good enough?

Factory water pump or does someone have a new improved model that doesn't fail after 40k miles?

Any "might as wells" that I should go ahead and take care of while it is all apart?

Thax for your input
Steve B.

N0DIH
03-01-05, 07:57 PM
What is the thoughts on changing the timing chain and gears? My "new" FWB is at 149K miles, runs good, but at that many miles, I would anticipate stretch, but what sort of stuff did you see?

Should I worry about it all? Chock it down as a summer project?

Are they steel gears now?

Thanks!
Tom

cadillacmike68
03-04-05, 12:46 AM
First, there's no cap / rotor of the LT1. That distro is going to cost you, I couldn't even stare at one for $200.00. morel like 400.:hmm:

Water pump, I got one at discount auto parts, new not reman, worked fine, I had the old one off to "match" and no problems after 50-60 thousand (original went about 100 thousand).

When a water pump fails, one of it's problems is that it will leak.

In GM's infinite wisdom, they designed a car where the water pump is directly over the 50 thousand volt ignition system, so that when it fails the distro gets trashed too. - Kind of reminds me of the late 60s -early 70s heater control valve, that when it failed, it sucked coolant into the climate control master control unit. :rant2:

Formula94lt1
03-21-05, 12:02 PM
For all GM parts talk to Jason Cromer in the parts departement... It is by far teh cheapest place, especially for a dealership, to get GM parts. You usually save money even over Gm parts direct with the shipping you save.... let me find the number because I got my 94 non-vented opti for 320 from him and apperantly people have been quoted as little as 270 dont know why I wasnt though, whatever. 1-877-726-8295

N0DIH
03-25-05, 11:39 AM
Any thoughts on why my 94 FWB has a vent tube (factory appearing)?

Did late 94's get the 95 engine? Or at least some 95 parts?

So does the vent tube save you from OS replacement if the WP leaks? Or just buys you a little time if you catch it right away?

Mine appears to be a 151K original OS and WP.

My thougts are do I do a WP/OS and timing chain swap all at once this summer as preventative maint? Heck, if I am going in that far, do I do a Z28 cam swap too just for fun? Being I have factory 3.42's, would the Z28 cam be a better match for my gears?

Tom

FASSTWOOD
03-30-05, 01:00 AM
The z28 cam will kill your torque, or whats left of it...

Katshot
03-30-05, 07:49 AM
The Z28 cam will have a negative impact on your low and mid-range torque, and you WILL notice it in your 4500lb car!
As for the timing chain/gears, yes, I'd do them at 140K miles. As for the overall design, I guess it "could" be better but I generally had little or no trouble in my fleet cars over the years, so I'd say the issue is a little over-blown. As for the vent tube(s), they were different in the '95 I think but you can use the newer version if you want. The newer version just does a better job of venting the distributor as I recall. The venting is more for the purpose of removing ozone and less for keeping it dry. The biggest problem we had on our fleet cars was when the vent tubes were damaged or left unhooked. Then water and other crap would get into the distributor and kill it. The single biggest problem we had with the distributors was the harness seal on the top failing and allowing water and crap to get in. This deteriorated the connectors on the plug and eventually the interior components of the distributor.

N0DIH
03-30-05, 08:44 AM
I emailed the cam specs on the B/D and the F/Y cars to a friend of mine and he agreed (he is in the Pontiac circles), the LSA is too wide and kills the torque. We are sort of puzzled why GM widened the LSA so much. 111 to 117? Even the 500 Caddy's were at 115 and that was thought to be huge. It was done for idle quality mainly, 117 seems extreme. He feels the Z28 cam with the 111 LSA would be a better choice. He would prefer a 108 or 106, but likely the ECM wouldn't be so thrilled.

I think if I do any changes it will be rockers, maybe, if the 1.6 roller rockers will fit stock springs, but likely not the cam.

But for the topic on hand, my timing chain and gears are factory stock, as is the water pump. So I think I will be saving up the parts to have on hand if it goes, plan for a swap by the end of the summer regardless. I don't have a garage yet, so winter car work sucks.

I guess I will have to get into it. From all the pictures I have seen my 94 has a 95 Optispark and front engine cover. My guess is GM switched over sometime in the model year to the 95 engine or at least, 95 parts on the 94 engine at one point.

How do I find out of the hose is plugged? I don't want to blow it out, as if there is junk in it, I don't want to spray all over in the Opti. Maybe temp plug the vent to the air intake and make it suck full vacuum for a moment? Or hook my vacuum pump up and make sure it doesn't hold a vacuum? There is some rusty residue in the intake tract, so it has pulled some rusty water up already. Is that a bad warning sign?

Thanks!