Advice needed on Cam belt, otter switch, doors, wiper please

[peter319]

Hi,
I've just bought and driven home in my first Excel. I've had a number of "interesting" cars before but am a Lotus virgin
So far she's travelled from Dover to Northumberland without a hiccup and I've been 20 miles each way to work today.
I've spotted the following items....so far!!!
Is it normal for the wiper to lift off the screen at anything over 90ish? Also the tops of the doors open at speed and the wind noise coming in is huge!
The oil pressure gauge has packed up but I'm hoping it's a simple job to replace as it happened just prior to my purchase (yeah right!) and a spare was included.
The cam belt was last changed in 2005 which is about 18000 miles ago....should I replace it for peace of mind and does it need to be a Lotus specialist doing it or can any competent mechanic manage it?
I got stuck in town on the way home yesterday and the temp gauge got to 100 ( the fans never cut in) before I pulled away again, I've read posts here that suggest the "otter" switch packs in fairly easily. Does this sound like my problem?
Finally,(you'll all be glad to hear!)......... the fresh air intake to the air filter is sited behind the radiator in a kind of semi-circular clip, surely it should be somewhere cold? Does this sound like a previous owner mod or is there another similar clip somewhere cooler for summer driving?
Sorry to sound so dumb but I'm a quick learner so if you are all kind enough to impart your collective wisdom I'll be able to stop with the stupid questions and move on to more technical stuff!
Thanks in advance for your help.

[Tanz]

Hi Peter,

The most worrying question for me is the cam belt. Lotus bits recommend changing it once a year. This may be too oftern for some people but cheaper than a new engine! Certainly at least every two years. You need to change it ASAP.

Fans should cut in at about 90. I would worry if I saw 100 on the temp gauge. Short the Otter switch and see if the fans come on. If they do then it must be the otter switch.

The air intake pipe does sit in a clip in a place that does not seem logical. I ran mine without a pipe for a while and it made no difference to the engine temperature so don't worry about it.

Cheers,

Phil

[peter319]

Thanks Phil, I'll get the belt changed asap!
I think I've seen the answer somewhere but can't seem to find it..."Where is the otter switch?"
I'lltry shorting the switch tomorrow at work as we have a motor vehicle section and I'll be changing the oil pressure gauge anyway. I'm still impressed with what seem to be minor niggles on a 22 year old "Norfolk turnip farmers" car!

[amarshall]

The otter switch should be in the top hose - it's visible in the photos on my "How to replace with a capillary thermal switch" page : http://www.ngate.plus.com/otter.html

Starting point for testing is to short across the otter terminals to see if the fans come on. If not - the fan fuses may have blown, or the fans themselves have failed.

What are the symptoms of your oil pressure gauge problem - does it read always 0 or high ?

If it's reading high, chances are that the connector on the oil pressure sender has come off. This is near the top of the engine, under the carbs, above the starter motor. You may need to remove the airbox to get to it, but the connector should be visible through the carbs looking towards the back of the engine.

Air intake - the clip actually sits just above the radiator to allow cold(ish) air in. There is a temperature controlled flap in the intake hose which opens if the ambient temperature is low to take warm air in from behind the rad.

Wipers lift. Always.
Door frames bow out. Always.

Welcome to TADTS syndrome

Oh - and did you buy from a dealer or was it private sale ? Dover is ringing some alarm bells...

[peter319]

Wow, you guys don't mess about!
I'll be in there tomorrow and hopefully report back soon with a "fully sorted" or at least a progress report.
Thanks for the pics angus, spot on and hopefully engine saving!

[Redexcel]

My two pence worth.

The temperature controlled flap in the intake is only fitted to very late cars. ('90 model year on?). It is present to prevent carb icing, which usually occurs when the ambient temp is a couple of degrees above freezing and at high humidity. The low temp causes a small thermostat to allow vacuum to reach the switch, thus switching to the alternative intake. There should be a large bore hose which goes across the top of the engine to connect to a shroud which fits around the exhaust pipe. This allows warm air to be drawn into the carbs and prevents icing. Most cars I have seen have had this pipe removed.

My temperature gauge has always reached approx 100 deg before the fans cut in (this may not mean the engine is really that hot, however) and in 13 years ownership, that has never caused a problem despite being caught in some awful jams in that time. It looks a little alarming at first, but you soon get used to it. Try letting the engine idle and watch the gauge, you may find the fans cut in when it reads about 100.

Does your oil gauge read from 0-5 or 0-7. Some cars left the factory with a 0-5 gauge fitted, when they should have had 0-7. Hence they read off-scale all the time the revs are above idle, even with a hot (and healthy) engine. I think this was fixed if customers complained, but quite a few cars never had the correct gauge fitted.

Some wind noise from the doors is normal, but it should only be a gentle hissing at about 70 MPH. If it's more, maybe some adjustment is called for. Not sure how though.

[peter319]

Hi Paul,
I'll let her get to 100 degrees and see what happens, I know the fan on my bike never cuts in until 110 degrees, I just assumed it should be cooler than this. Oh well here goes nothing......
My oil pressure gauge is 0-5 bar. I'll try the new 0-5 and if it does sit over the top I'll buy a 0-7. Will Lotus do the swap as a recall after 22 years? ?
As for the pipe to the air filter, it is very large bore (about 3-4 inches at a guess) and runs from the airbox, across the top rear of the engine and down to a clip behind the rad fans. It ends in a sort of rubber trumpet (the trumpet bell being inside the pipe). I'll take a pic and post it here as I'm sure everyone will then say "they have all got one the same" and I'm just being a total dumbass!

[Steve C]

The otter switch should cut the fans in at 90 degrees and drop out again around 87 degress .. if it doesn't do something close to that I'd investigate sooner rather than later - even though it shouldn't boil at 100 due to the pressure in the cooling system raising boiling temp, if the cap is leaking or something like that, there's a chance it will. I've replaced the otter switch in mine twice in the last 100k miles, once when it was causing the fan relay to buzz, another time when the cut in temp was creeping up.

The hot air hose on the '90 spec cars tends to fall to pieces and ends up not being replaced because it was pretty expensive from Lotus. On very rare occasions I get carb icing, maybe once a year. If it happens, stop the engine for a couple of mins, the heat soak melts the ice and it's fine after that!

The 0-5 and 0-7 gauges have matching sender units, make sure you get the one that matches the gauge or the readout will be meaningless! My car came out of the factory with a 7 bar gauge but the sender went faulty. Lotus didn't have any 7 bar senders at the time so the dealer fitted a 5 bar sender and 5 bar gauge. Hot idle on mine is around 2.5 bar, hot at cruising speeds around 4.5 bar+ depending on revs, cold it's pegged at 5 bar or a little over. I use this as a thrashability indicator .. when the oil pressure at idle has dropped to 2.5 bar, its nice and warm. This takes much longer than getting the water to the 82 deg stat opening temp!
Oh, and those figures are on my 153k mile engine .. so yours may vary a little!

You might want to check the fans spin by hand ... after an off the road period a while back, one of mine stuck and caused a fuse to blow ...

Welcome to the madhouse!

[Redexcel]

Hi Paul,
As for the pipe to the air filter, it is very large bore (about 3-4 inches at a guess) and runs from the airbox, across the top rear of the engine and down to a clip behind the rad fans. It ends in a sort of rubber trumpet (the trumpet bell being inside the pipe). I'll take a pic and post it here as I'm sure everyone will then say "they have all got one the same" and I'm just being a total dumbass!

Odd, if your car doesn't have the vacuum activated flap, it should just have a length of trunking going forward and curling around in front of the engine/behind fans and resting in the semi-circular clip as you have described. It does end in a sort of rubber bellmouth.

My fan relay does chatter for about half a second when it is switching. Maybe I need a new otter switch.

[Steve C]

The brief chatter of the relay seems to always be there on my car ... the faulty otter would cause the buzz for 5 secs or more. I'm still surprised at the switching temperature of yours though... Maybe worth checking with one of those infra-red temp sensors to work out if it's a dodgy temperature sender / gauge or the otter at fault.

[Sooty]

There's a funny thing. My rad relay chatters too. Off to Sj's for replacement.
Wayne

[bash]

On the subject of relays, Ive had my car a number of years, and, contrary to the misinformed opinions of most classic mags, the electrics have been quite reliable ( famous last words! ). But, whoever thought of putting the relays above where the drivers wet feet go wants a kick in the posterior. I have had a couple of wierd defects over the years, always related to the relays getting corrosion in them. If you have any chattering relays put your finger on the case to find out which one it is and replace with a new un. Eventually the chatterring will stop if you dont do this and it may strand you. Because of this I always carry a spare relay. They are pretty standard items available at any motor spares shop..

Bash

[Wingnut]

causing the fan relay to buzz

Wondered what it was making the relay buzz as the fans came on. Off to purchase a new otter

[peter319]

Hi again.......
I've just noticed Angus' "Oh - and did you buy from a dealer or was it private sale ? Dover is ringing some alarm bells..."
Er, I bought privately.....is there something I should know?!!? I'm happy to PM the car details if you think there there is something amiss.
Anyway, the new oil pressure gauge is in and sits at 2-2.5 bar on a hot idle. Anything above idle and it goes up to 5 bar (max) and stays there until the revs drop to idle again. I've seen on the forum that Lotus recalled cars to change to a 7 bar gauge, will they do a recall for the swap on a 22 year old?
As for the otter switch....... firstly lets get things straight....I'm a bit of an eejit when it comes to electrics! When you say "short across the otter switch terminals what do I do? Short the two connectors that go to the fans? Short the terminals on the actual switch? With the leads to the fans attached or not? I've only got a finite number of 10A fuses
Other niggles are that the clock and ciggy lighter don't work.....I know they are on the same fuse but the fuse is fine, it may just be a coincidence that they are both Kaput!
Can anyone recommend somewhere for a service, cam belt change and general check over that isn't A: too far from Northumberland and B: too expensive?
Thanks guys

[Steve C]

Pull the two connectors from the otter switch and touch them together with the ignition switched on. Do NOT short the wires to the fans or you will need another 10amp fuse ...