Ok this is a bit of a rant thread but not one that would qualify for the normal rant thread. This past weekend I decided to change the valve cover gasket on my 2006 Mazda 3 since I noticed when I got it quite a bit of silicone sealer poking out from under it. I figured someone had just used the sealer in lieu of a gasket for a quick fix without access to the part. I knew going in that I would be removing a bit of silicone but figured it would all or mostly be in the recess in the valve cover. So I get the cover off to reveal that they had not replaced the gasket and just went around all of the top sealing surfaces of the head with sealant. Really? of course the old gasket was probably original (145k miles) because it was hard as a rock but it was still in there, which means instead of peeling out the silicone from the valve cover most of the sealant was on the top of the head. If you are going to "fix" a valve cover gasket just do it! Why would you go though all the labor of doing all the steps to swap the gasket and then not do it? It's a 2006 Mazda not a 1976 Maserati, the gasket is readily available for $14 and take about 30 seconds to swap out. So this leads me to 4 hours of bending over the top of the engine carefully removing all the sealant (so as not to have any bits get into the head) and provide a clean sealing surface for the gasket. Turned a half hour job into a 4 hour job for no reason other then fixing something half assed. At least is properly fixed now. I hate following hacks.
Clean that stuff off with a shop vac hose in one hand and a gasket scraper in the other. Goes much easier than trying to carefully not get any crap down where you can't get it back out.
There really should be licensing requirements for buying RTV.
NEALSMO
UltraDork
4/3/17 11:00 a.m.
As a professional this drives me nuts. Good way to kill all profit from a job having to scrape previous idiot's silicone off.
Seriously, the purchase price of a new gasket is so minor compared to the labor involved.
NEALSMO wrote:
As a professional this drives me nuts. Good way to kill all profit from a job having to scrape previous idiot's silicone off.
Seriously, the purchase price of a new gasket is so minor compared to the labor involved.
Yeah, but the original gasket failed after just 120,000 miles! Who has 20 minutes to swap a valve cover gasket every 120,000?! This done fixed it right, aw he!
NEALSMO wrote:
Seriously, the purchase price of a new gasket is so minor compared to the labor involved.
Yep. But every once in a while, you find a situation where RTV just works better.
Case in point: intake manifold end seals on older American V8s (the gaskets are sometimes a hair too thick and prevent the manifold from setting down far enough for the side gaskets to seal but RTV works perfectly).
Same goes for the heater return tube to the water pump on my Jeep. Using the correct factory o-ring has never failed to produce a significant leak. Smearing the end of the tube heavily in RTV and installing it without the o-ring works great.
codrus
SuperDork
4/3/17 11:31 a.m.
There's also the scary possibility that the reason he didn't have a gasket sitting around is that he wasn't fixing a leak -- he went under the valve cover to do something ELSE in there...
Tk8398
New Reader
4/3/17 12:22 p.m.
I had to do that on my moms toyota 4 runner, it took hours to scrape all the rtv off.
We're always amazed here at the lengths some people will go to in order to do a job poorly.
Says the guy who opens his trunk with a piece of speaker wire tied to the anti-trap handle because there's a little piece of broken plastic on the latch and I keep forgetting to go to Jim Ellis Volvo and find the part number and order it.
RTV: making E36 M3ty mechanics look competent for years.
Not sure how common this is but on the Impulse RS part of the shop manual procedures for the valve covers is to use a normal gasket but also apply RTV to a couple key spots.
I have to ask, was it actually leaking or did you not like the look of the RTV?
In reply to Maniac0301:
That's pretty typical, e.g. on a OHC engine with a timing chain you often need just a dab at the two points where the timing chain case meets the head. I think the last valve cover gasket I bought included a small tube for that purpose.
Maniac0301 wrote:
Not sure how common this is but on the Impulse RS part of the shop manual procedures for the valve covers is to use a normal gasket but also apply RTV to a couple key spots.
It is for this one too, but only two very tiny parts where the timing cover meets the head. all the rest is a (normally easy to replace) rubber gasket.
rslifkin wrote:
NEALSMO wrote:
Seriously, the purchase price of a new gasket is so minor compared to the labor involved.
Yep. But every once in a while, you find a situation where RTV just works better.
Case in point: intake manifold end seals on older American V8s (the gaskets are sometimes a hair too thick and prevent the manifold from setting down far enough for the side gaskets to seal but RTV works perfectly).
Same goes for the heater return tube to the water pump on my Jeep. Using the correct factory o-ring has never failed to produce a significant leak. Smearing the end of the tube heavily in RTV and installing it without the o-ring works great.
And rear differential covers on Ford 8.8s.
Toyman01 wrote:
I have to ask, was it actually leaking or did you not like the look of the RTV?
Actually both, when I bought the car I made a mental note that it looked like they had used RTV in lieu of a gasket so prepared to put a proper one in there and then the other day noticed it was seeping in places out from under the RTV, so I decided to move the job up in prioritys to do this past weekend. In the end using nothing but RTV would have been better because the old gasket was hard as a rock and not sealing evenly so just having the RTV under the old gasket was only slightly better then nothing at all. Just was stupid to go through every step to replace the gasket only not to.
If I had done this at a shop I would have billed the guy for 5 hours, and I'm sure they would have been pissed at paying ~$500 for a valve cover gasket change....
In reply to Rumnhammer:
I don't disagree that fixing other peoples hack jobs can be annoying at best. That is doubly true when fixing it correctly is just as easy as the hack job they did.
D2W
Reader
4/3/17 4:04 p.m.
Overuse of RTV is better than JB weld used as a permanent gasket.
hey man, no need to hate me :b
I just wanted to tank you for this thread. I noticed a pretty big leak from the timing belt area on my miata yesterday. I automatically assumed the worst. This thread made me realize that I forgot to rtv the corners of the valve cover gasket.
I offen like to think that the job was done poorly out of necessity. I know I am guilty of that more tan a couple times. Or the previous owner did not know anything about cars really and went to the local pepadvancedzoneboys and the nice kid advised said person to use RTV either because it was cheaper or they did not have the gasket in stock. Not knowing better they used it. The really scary part is now they may think that they are actually qualified to "fix" other things. But hay everyone has to start someplace.
c0rbin9
New Reader
4/3/17 7:56 p.m.
Is this now a whining about POs thread? I sure hope so.
Hack-jobs I've ran into on my E30:
-radio power wires stuffed into fuse box
-roll hoop bolted to floor pan
-tar insulation crap everywhere
-spray foam in trunk lid
-cheap aftermarket carpet laid over old OEM carpet
-battery held down with bungie cord
-shift knob epoxied on
I even made it into a list to piss me off further.
In reply to c0rbin9:
Next time I run into a hackjob that was more complicated and expensive than just fixing it right, I'll post in this thread. It shouldn't take too long.
Okay, I got one that I remember from last week. Cheap auto parts store oil filler cap on a Ford that, predictably, leaked. So it was artfully given a cardboard gasket, which was ugly and also still leaked. So a rag was tied around it.
A new oil filler cap, from Ford, is like $6 list.
One of my favorites than I ran into a few years ago. Guy needed a signal to his trailer brake booster controller so he ran a wire from the dash all the way back to the tail light and another back to the dash. The brake switch was 7 inches away from where he mounted his controller. I measured for my own entertainment.
BrokenYugo wrote:
There really should be licensing requirements for buying RTV.
There also really should be licensing requirements for buying basic automotive tools.