Poll on Head gasket problems (1 Viewer)

[parabola]

Well, with all this talk of HG issues, I decided to take a look at my PHH. Wow. It's not leaking yet but it ain't pretty looking. It's bulging like ... well I can't think of anything non-obscene to say here.

Looks like I'm going to have to go ahead and set aside a couple hours for my planned coolant flush so I can go ahead and replace this darned thing.

This is on a lifetime Lexus maintained truck with 101K miles. Everyone, take at look at your PHH!

http://www.sleeoffroad.com/technical/tz_heater_hose.htm

 

[wsdavies]

15% failure rate...seems a bit high to me

 

[e9999]

It's been at 15% or so for a while now.
I think this is a big enough sample that we got to accept the #s, distasteful as this may be.
I will do a poll on trying to figure out the cause / symptoms in a bit. More later.

This is disconcerting!
It may well be that this a problem that is easy to avoid, but otherwise would you buy a top of the line truck if you were told there is a 15% chance the HG will go on you before 150K or so?

 

[MH_Stevens]

Might I be so bold to ask those 14 people who have reported HG failure to respond with a brief synopsis of what happened, to include: Did you have prior overheating? If so, why and how long before failure? What warning if any of failure was there? Your milage when failure occured? Point of failure - was it #6?

 

[MoJ]

Is there a failed HG by year poll out there?

 

[Farley]

I'm at 113,000 on my LC and don't really know if the HG blew. I bought my 97 with 111,000 miles and It appears that the PO had kept up on the maintinance - at 90,000 he had done a coolant flush (among other maint items) and I did another flush at 111,800. I had a reputible Toyota mechanic check all the hoses when they did the flush and was told that everything looked good.

Is there a way to check the PHH without removing the DS tire - not that it's a problem - but I was wondering if it was possible. Also is there any way by looking at the head to tell if the gasket had already been changed - or to get a service history using the VIN?

 

[e9999]

I'm at 113,000 on my LC and don't really know if the HG blew. I bought my 97 with 111,000 miles and It appears that the PO had kept up on the maintinance - at 90,000 he had done a coolant flush (among other maint items) and I did another flush at 111,800. I had a reputible Toyota mechanic check all the hoses when they did the flush and was told that everything looked good.

Is there a way to check the PHH without removing the DS tire - not that it's a problem - but I was wondering if it was possible. Also is there any way by looking at the head to tell if the gasket had already been changed - or to get a service history using the VIN?

well, this poll is assuming that you know for a fact that it blew either on your watch or before. If there is no evidence to contrary just assume it never blew.

I vaguely remember something about checking the sealer goop in the front where there is this round shape, presumably to tell if it has been opened up or not. Or maybe the gasket edge is visible someplace and one could tell from the shape or color?

 

[flintknapper]

Is there a failed HG by year poll out there?

I'm not sure it would prove anything conclusive.

It seems most of the members that have responded have later model units (95-97), quite naturally the poll will show that statistically these vehicles are most troublesome. In order for us to know (with any certainty)..we would have to have a like number of other year models to compare against.

Even then...you couldn't say that the maintenance history of each is comparable.

An informal poll of this nature can only reveal that some number of people have HG issues. The number of people responding is too small IMO to try to extrapolate an accurate percentage figure.

I believe the discussion concerning possible causes is of more value.

But.......polls are fun, and this one was nicely done.

 

[MH_Stevens]

I
Also is there any way by looking at the head to tell if the gasket had already been changed - or to get a service history using the VIN?

I believe there is. The factory uses a light grey sealant that bulges out in distinctive pattern. There are pictures on this forum somewhere.

 

[e9999]

16/113 = 14%
Has stayed at a constant ratio for a while.
This is a lot folks!

One conclusion already seems to be that this is not strictly a mileage or age related problem. Statistically this looks more like a random event. Or could be maintenance related.

A corollary is that one should not feel safe because their rig is low mileage!




I'm tellin' ya, I'm keeping a close eye on this cooling system.

Action items for me to do from now on:
- Flush coolant seriously regularly
- Check fan clutch regularly
- Check for bubbles regularly
- check for crusties regularly
- check the overflow level regularly for loss
- replace rad cap and thermostat regularly
- Install and use actual temperature measurements in the cab, with an alarm (see other post)

I don't want mine to blow!

 

[e9999]

Since the second part of this poll is a bust, I have started another poll to try and shed some light on how the maintenance history and condition may have affected things.

Those of you who had a blown HG, please be kind enough to vote in this other poll - thanks!

btt for newbs...

 

[MoJ]

I'm not sure it would prove anything conclusive.

It seems most of the members that have responded have later model units (95-97), quite naturally the poll will show that statistically these vehicles are most troublesome. In order for us to know (with any certainty)..we would have to have a like number of other year models to compare against.

Not at all necessary to have a like number of each year if you have a reasonable sample size of each. Think percentage rather than raw count.

 

[flintknapper]

????

Not at all necessary to have a like number of each year if you have a reasonable sample size of each. Think percentage rather than raw count.

O.K. how do you separate the two. Aren't percentages drawn from the raw numbers?

 

[e9999]

right, you need to look at the "year" poll number at the same time to make sense of this.
If 97s are 30% of the rigs here, say, what matters is if there is more or less than 30% of headgaskets busted for that year... that would tell us if there is something wrong with the 97 and/or if there is a mileage issue.

 

[MoJ]

O.K. how do you separate the two. Aren't percentages drawn from the raw numbers?

Pretty much do it as E described --- However, you could also do a poll by year by blown/not blown and then look at the failure rate by year. You may be confusing an attempt to say "x % of all blown HG's are year 199X" as opposed to a poll designed to come up with a conclusion such as "x % of 199X suffered failed HG's." The second would give you the ability to determine if one year or another suffers from a higher rate of failure. Of course all that depends on having a decent sample size/response rate and the assumption that the study meets "statictically significant" criteria (which it likely won't but would still give us a rough idea).

 

[Bob_Garrett]

Might also be interesting to see what percentage of the headgasket failures were on turboed or supercharged engines.

Bob

 

[Dansan]

95LC, 120K miles, no HG issues as yet. Cooling system has been prety well maitained.

I read some but not all of the posts and was wondering if any filter was in place to determine whether the rigs with HG failures were 1st, 2nd or subsequent owners?

I bring this up because of the maintenance issue. If someone bought my rig or from a lot of other people here, they would get evidence of excellent maintenance. I contend that a lot of these rigs were originally bought for vanity and reputation but as soon as the purchaser got a whiff of the Toyota dealer's service charges, they backed off on PM. This would be easy to do because the truck would be flawless through at least 50K with minimal maintenance.

The problem then occurs for someone who gets on of these, between 7 and 12 years old, with minimal maintenance. IdahoDoug has pretty relentless cooling system maintenance and I'm inclined to believe that will make HG failures rare.

So, as a curiosity, it might be interesting to know how many owners the vehicles with failed HG's had and if they had very clear service records.

 

[e9999]

btt

and again for the last 2 or 3 cases...

 

[lahar50]

103,000 and no problems yet and I hope it stays that way.

 

[e9999]

of course, there is a flaw in this poll, and that is if -god forbid- you (not me, no, no, not me, not at all, never, ever, absolutely not, can't happen....) end up losing your gasket but you have already entered no problem then you'll have 2 votes... oh well, still useful to know roughly how many and especially when they failed...